Which of the following was once a volcano under the ocean?
a. sea stack
b. cave
c. ocean trench
d. seamount

The correct answer is (d.) seamount. A seamount is a mountain rising from an ocean floor, however, it does not reach the water surface, thus, it is not considered as an island or whatsoever. It was indeed once a volcano under the ocean.

#1 answer = C
#2 answer = A
#3 answer = D

well number 1 is C because our universe has been expanding ever since the big bang theory and thats what it claims as well. 
number 2  is A well the answer is the explanation:)
and number 3 is D because if you look up the word kinetic it says:of, relating to, or resulting from motion.
so have you ever seen those wind turbines? well they create energy from movement and being pushed by the wind:)
hope this helps 
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