Antonym of QUIESCENT

Answer: Option A

Quiescent : in a state or period of inactivity or dormancy.
Troublesome : causing difficulty or annoyance.
Weak : lacking the power to perform physically demanding tasks; having little physical strength or energy.
Indifferent : having no particular interest or sympathy; unconcerned.
Unconcerned : showing a lack of worry or interest, especially when this is surprising or callous.

Antonym of Quiescent is Troublesome