B one dar ......... piper
Answer:
D
Explanation:
Feeling excessively sad or low. Confused thinking or problems concentrating and learning. Extreme mood changes, including uncontrollable “highs” or feelings of euphoria. Prolonged or strong feelings of irritability or anger. - nami.org
these would all cause sudden changes in behaviour
Meaning of experiment is A-controlled observation.
Part A: D
Part B: A
