Answer:
B. extrusive
Explanation:
Extrusive igneous rocks -
The composition of these rocks are finely grained , as the during the process of crystallization , the minerals does not get enough time to crystallize .
As , these rocks are rapidly cooled , and during rapid cooling , the fine grained of rocks are formed .
In case of slow cooling , the rocks generally have , coarse grained .
Hence , the correct answer is B. extrusive .
