Task: Question Answering
Input (English): Background Paragraph: Magnetism is the ability of a material to be attracted by a magnet and to act as a magnet. Magnetism is due to the movement of electrons within atoms of matter. When electrons spin around the nucleus of an atom, it causes the atom to become a tiny magnet, with north and south poles and a magnetic field. In most materials, the north and south poles of atoms point in all different directions, so overall the material is not magnetic. Examples of nonmagnetic materials include wood, glass, plastic, paper, copper, and aluminum. These materials are not attracted to magnets and cannot become magnets. 
Story: Rob got a compass as a present for his birthday. The magnet in the compass made him very interested in how magnets work. To understand magnets better he categorized objects in two groups, group A and group B. In group A all objects were magnetic, but in group B none of the objects was magnetic. 
Question: Which group's objets might not include paper or plastic, group A or group B?
Output (English): group A.