The correct response regarding how a mountain range helps investigate why there’s a dry climate on the leeward side of it is:
Mountain ranges can create rainshadow deserts.
This phenomenon occurs when moist air rises over the windward side of the mountain range, cools, and loses moisture in the form of precipitation. As the air descends on the leeward side, it warms and becomes drier, leading to a desert-like climate. This process is known as the rainshadow effect.