The correct answer is: C. copper
Copper is a good conductor of electricity, which is why it is used in CPU chips. It is also a relatively soft metal, which makes it easy to work with.
Silica is a type of sand that is used in many different products, including glass, concrete, and ceramics. It is not a good conductor of electricity, so it is not used in CPU chips.
Carbon is the main component of coal, oil, and natural gas. It is also the main component of diamonds. Carbon is not a good conductor of electricity, so it is not used in CPU chips.
Gold is a very expensive metal that is used in jewelry and other decorative items. It is also a good conductor of electricity, but it is not as good as copper. Gold is also a very soft metal, which makes it difficult to work with.
Silver is a good conductor of electricity, but it is more expensive than copper. It is also a softer metal than copper, which makes it more difficult to work with.
In conclusion, the correct answer is: C. copper