Here, we can see in the given picture, The lowest temperature was observed in the Mesophere layer. The temperature is gradually decreasing from 0°C to -100°C(approx.) as the altitude increases. So we can say that,
Appropriate Answer:-
The mesosphere tends to get colder at higher altitudes.

Rest options are not correct because of the wrong observation and reason provided which are matching to the predictions made from the picture.
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