Plants that live in hot, dry climates have evolved mechanisms to help conserve limited water supplies. One example is the closing of leaf openings by guard cells during the day to decrease water loss from their leaves. This detection of and response to an environmental stimulus is an example of

feedback mechanism

Explanation:

Feedback mechanism: In biology, the term "feedback mechanism" is described as a physiological loop that is responsible for bringing up the body either away or towards the steady or normal state. The feedback mechanism is also denoted as "feedback loop" and is responsible for either inhibiting or amplifying a specific biological pathway. Therefore, these pathways tend to return the body towards "homeostasis".

In the question above, the given statement is an example of a "feedback mechanism".