The answer would be: <u>Molten material that cooled quickly.</u>
Igneous rocks are formed by the cooling of molten material. So we can cross out the last two choices. The rock has no identifiable crystals so it is most likely an Extrusive igneous rock. They form on the surface where they cool quickly.
Those that form underground are called intrusive rocks. They cool slowly allowing enough time for crystal formation.
I think the correct answer from the choices listed above is option C. Cells in multicellular organisms differentiate as they continue to divide and increase in size because cells will now perform special functions and have become different to other cells. Hope this answers the question.
The best answer to the question above would be letter d. The sentence presented which is 'Researchers helped further the biological perspective when they demonstrated that electrical stimulation of the brain could evoke emotional responses in animals.' demonstrates how new discoveries can influence perspectives.
