Question

18. When magma cools quickly, what kind of texture or crystals does a rock have? A. Coarse-grained or large crystals. B. Medium-grained or medium crystals. C. Fine-grained or small crystals. D. A mixture of all types of grains. E. A mixture of all types of crystals.

Answer 1

Answer:

C. Fine-grained or small crystals.

Explanation:

When the rocks are rapidly cooled , and during rapid cooling , the fine grained of rocks are formed  , as during the process of crystallization , the minerals does not get enough time to crystallize and forms a small and fine - grained crystals .

And ,  

In case of slow cooling , the rocks generally have , coarse grained .