Question

select the correct answer.
what are comets composed of?
a. iron
b. silicon
c. ice and dust
d. oxygen and nitrogen

Explanation:

Comets are often referred to as "dirty snowballs". They are composed of ice (which can be water - ice, but also ices of other substances like carbon dioxide, ammonia, etc.) and dust. Iron is more commonly found in the cores of planets like Earth. Silicon is a major component of rocks on Earth and in rocky planets. Oxygen and nitrogen in the form of gases (like in Earth's atmosphere) are not the main components of comets.

Answer:

C. ice and dust