The correct answer is B.
Freezing of glaciers would do absolutely nothing to the salinity, as for hot weather and evaporation would leave behind the salt and thus INCREASING the amount of salt to water in the ocean.
Mitochondria is the correct answer
Answer: C. A snake hides under a rock on a hot day.
Explanation:
Thirst, hunger, and pathogens are internal issues (meaning inside of the body). Weather (heat) is something from the external environment that the snake is responding to (hiding). Therefore, the correct option is C.
Let me know if you have any questions!
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<em>Question: Which behavior is a response to an external stimulus?</em>
<em>A. A dog drinks to quench its thirst.</em>
<em>B. A squirrel eats when it is hungry.</em>
<em>C. A snake hides under a rock on a hot day.</em>
<em>D. A cat vomits to rid itself of pathogens.</em>