Compared to the valley, the ridge is relatively wet and warm. Compared to the valley, the ridge has exactly the same weather. Compared to the valley, the ridge is relatively dry and warm. Compared to the valley, the ridge is relatively wet and cool. Compared to the valley, the ridge is relatively dry and cool.

Compared to the valley, the ridge is relatively wet and cool.

Explanation:

The ridge is relatively wet and cool in comparison with the valley. Due to the mountains that surround the valley, the cool air does not enter the valley. This makes the valley hotter in contrast with the ridge. Also, it makes the ridge wet owing to the pressure and the low temperature that the air has.

i'm sure the answer you are looking for would be

a. an ice age

hope this contact me if this didn't or you need with more answers : )