Please answer the following question: Information: - A building or edifice is a structure with a roof and walls standing more or less permanently in one place, such as a house or factory. Buildings come in a variety of sizes, shapes and functions, and have been adapted throughout history for a wide number of factors, from building materials available, to weather conditions, to land prices, ground conditions, specific uses and aesthetic reasons. To better understand the term "building" compare the list of nonbuilding structures. - A pioneer ( / pa.nr / ) is a soldier employed to perform engineering and construction tasks . The term is in principle similar to sapper . Pioneers were originally part of the artillery branch of European armies . Subsequently , they formed part of the engineering branch , the logistic branch , part of the infantry ; or even comprised a branch in their own right . Historically , the primary role of pioneer units was to assist other arms in tasks such as the construction of field fortifications , military camps , bridges and roads . Prior to and during the First World War , pioneers were often engaged in the construction and repair of military railways . During the 20th century , British Commonwealth military forces came to distinguish between small units of '' assault pioneers '' belonging to infantry regiments and separate pioneer units ( as in the former Royal Pioneer Corps ) . The United States Marine Corps has sometimes organized its sappers into '' Pioneer Battalions '' . - A combat engineer (also called field engineer, pioneer or sapper in many armies) is a soldier who performs a variety of construction and demolition tasks under combat conditions. - Military engineering is loosely defined as the art and practice of designing and building military works and maintaining lines of military transport and communications. Military engineers are also responsible for logistics behind military tactics. Modern military engineering differs from civil engineering. In the 20th and 21st centuries, military engineering also includes other engineering disciplines such as mechanical and electrical engineering techniques. - Design is the creation of a plan or convention for the construction of an object, system or measurable human interaction (as in architectural blueprints, engineering drawings, business processes, circuit diagrams, and sewing patterns). Design has different connotations in different fields (see design disciplines below). In some cases, the direct construction of an object (as in pottery, engineering, management, coding, and graphic design) is also considered to be design. - Mathematics (from Greek "mathma", knowledge, study, learning) is the study of topics such as quantity (numbers), structure, space, and change. There is a range of views among mathematicians and philosophers as to the exact scope and definition of mathematics. - A sapper, also called pioneer or combat engineer, is a combatant or soldier who performs a variety of military engineering duties such as breaching, demolitions, bridge-building, laying or clearing minefields, field defenses as well as building, road and airfield construction and repair. They are also trained to serve as infantry personnel in defensive and offensive operations. A sapper's duties are devoted to tasks involving facilitating movement, defence and survival of allied forces and impeding those of enemies. - A combatant is a person who takes a direct part in the hostilities of an armed conflict. If a combatant follows the law of war, then he or she is considered a privileged combatant and upon capture, he or she will qualify as a prisoner of war under the Third Geneva Convention (GCIII). An unprivileged combatant is a person, such as a mercenary, who takes a direct part in the hostilities but who upon capture does not qualify for prisoner-of-war status. - Construction is the process of constructing a building or infrastructure. Construction differs from manufacturing in that manufacturing typically involves mass production of similar items without a designated purchaser, while construction typically takes place on location for a known client. Construction as an industry comprises six to nine percent of the gross domestic product of developed countries. Construction starts with planning, design, and financing; and continues until the project is built and ready for use. - Engineers design materials, structures, and systems while considering the limitations imposed by practicality, regulation, safety, and cost. The word "engineer ("from the Latin "ingeniator"")" is derived from the Latin words "ingeniare" ("to contrive, devise") and "ingenium" ("cleverness"). The foundation education of an engineer is typically a 4-year bachelor's degree or in some countries, a master's degree in an engineering discipline plus 46 years peer-reviewed professional practice culminating in a project report or thesis. Engineers who seek a professional engineer license in N. America will be required to take further exams in ethics, law and professional practice. - Knowledge is a familiarity, awareness or understanding of someone or something, such as facts, information, descriptions, or skills, which is acquired through experience or education by perceiving, discovering, or learning. - Infantry is the general branch of an army that engages in military combat on foot. As the troops who engage with the enemy in close-ranged combat, infantry units bear the largest brunt of warfare and typically suffer the greatest number of casualties during a military campaign. Historically, as the oldest branch of the combat arms, the infantry are the tip of the spear of a modern army, and continually undergo training that is typically more physically demanding and psychologically stressful than that of any other branch of the combat arms. Common representations of infantry fighting forces include the U.S. Army Infantry Branch, U.S. Marine Corps Infantry, Royal Canadian Infantry Corps, Infantry of the British Army, and the Royal Australian Corps of Infantry. - Industry is the production of goods or related services within an economy. The major source of revenue of a group or company is the indicator of its relevant industry. When a large group has multiple sources of revenue generation, it is considered to be working in different industries. Manufacturing industry became a key sector of production and labour in European and North American countries during the Industrial Revolution, upsetting previous mercantile and feudal economies. This came through many successive rapid advances in technology, such as the production of steel and coal. - Engineering is the application of mathematics and scientific, economic, social, and practical knowledge in order to invent, innovate, design, build, maintain, research, and improve structures, machines, tools, systems, components, materials, processes, solutions, and organizations. - In contemporary business and science, a project is an individual or collaborative enterprise, possibly involving research or design, that is carefully planned, usually by the project assigned team, to achieve a particular aim. After reading the paragraphs above, we are interested in knowing the entity with which 'pioneer ' exhibits the relationship of 'field of this profession'. Find the answer from the choices below. Choices: - combat - construction - design - education - engineering - graphic design - history - law - mathematics - military - military engineering - research - revolution - science - sewing - training - war
A:
military engineering