Answer:
C. Closure of stomata
Step-by-step explanation:
Abscisic acid (aka ABA) is a plant hormone that plays a role in the stress response, particularly in response to water stress.
When a plant senses that water is in short supply, it produces more ABA, which then signals the plant to close its stomata (small openings on leaves that allow for gas exchange) in order to conserve water and prevent dehydration. So, out of the options given, the promotion of closure of stomata is the response that is promoted by abscisic acid as a part of stress response.
option D is partly correct, but it's not specific enough to identify the role of ABA