How would a geologist identify an igneous rock as extrusive?
a.
an extrusive rock is coarse-grained because it cooled slowly beneath the earth’s surface.
b.
an extrusive rock is fine-grained because it cooled quickly on the earth’s surface.
c.
an extrusive rock is fine-grained because it cooled quickly beneath the earth’s surface.
d.
an extrusive rock is coarse-grained because it cooled slowly on the earth’s surface.