Answer:
your mark is correct
Explanation:
The marked answer choice is correct.
(2, -18) is not a global minimum, because there are function values that are lower.
(0, -6) is not a global maximum, because there are function values that are higher.
A global maximum is also a local maximum.*
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* More correctly, a global maximum is either a local maximum or the end point of an interval. No intervals are involved in this question.