Answer the following question given this paragraph: 

A metal is an element that is a good conductor of heat and electricity. Metals are also malleable, which means that they can be hammered into very thin sheets without breaking, and ductile, which means that they can be drawn into wires. When a fresh surface of any metal is exposed, it will be very shiny, because it reflects light well. This property is referred to as luster. All metals are solid at room temperature except mercury (Hg), which is a liquid. The melting points of different metals vary widely. Mercury has the lowest melting point of all pure metals (−39°C), and tungsten (W) has the highest (3422°C). On the periodic table in Figure above , the metals are shaded blue and are located to the left of the bold stair-step line. About 80 percent of the elements are metals (see examples in Figure below ).


Q: Which metal is not a solid even at room temperature?

 Choices:

- iron

- copper

- aluminum

- mercury

A:
mercury
