This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.

Input: Consider Input: Many applications of silicate glasses derive from their optical transparency, which gives rise to one of silicate glasses' primary uses as window panes. Glass will transmit, reflect and refract light; these qualities can be enhanced by cutting and polishing to make optical lenses, prisms, fine glassware, and optical fibers for high speed data transmission by light. Glass can be colored by adding metallic salts, and can also be painted and printed with vitreous enamels. These qualities have led to the extensive use of glass in the manufacture of art objects and in particular, stained glass windows. Although brittle, silicate glass is extremely durable, and many examples of glass fragments exist from early glass-making cultures. Because glass can be formed or molded into any shape, and also because it is a sterile product, it has been traditionally used for vessels: bowls, vases, bottles, jars and drinking glasses. In its most solid forms it has also been used for paperweights, marbles, and beads. When extruded as glass fiber and matted as glass wool in a way to trap air, it becomes a thermal insulating material, and when these glass fibers are embedded into an organic polymer plastic, they are a key structural reinforcement part of the composite material fiberglass. Some objects historically were so commonly made of silicate glass that they are simply called by the name of the material, such as drinking glasses and reading glasses.

Output: What ingredient makes glass colorful?


Input: Consider Input: The Juscelino Kubitschek bridge, also known as the 'President JK Bridge' or the 'JK Bridge', crosses Lake Paranoá in Brasília. It is named after Juscelino Kubitschek de Oliveira, former president of Brazil. It was designed by architect Alexandre Chan and structural engineer Mário Vila Verde. Chan won the Gustav Lindenthal Medal for this project at the 2003 International Bridge Conference in Pittsburgh due to "...outstanding achievement demonstrating harmony with the environment, aesthetic merit and successful community participation".

Output: What is the JK Bridge a nickname for?


Input: Consider Input: These 4G languages are less procedural than 3G languages. The benefit of 4GL is that it provides ways to obtain information without requiring the direct help of a programmer. Example of 4GL is SQL.


Output: An example of a 4GL is what?