Option 1: lethargic -> means sluggish and lacking energy, which is a synonym of listless, not an opposite.
Option 2: placating -> means soothing or appeasing someone's anger, unrelated to energy levels or enthusiasm.
Option 3: garrulous -> means excessively talkative about trivial matters, unrelated to engagement or energy.
Option 4: solicitous -> means showing eager care, attentiveness, and concern, the opposite of listless.
Hence, Option 4: solicitous -> "Listless" means lacking energy and enthusiasm, while "solicitous" means attentive, caring, and actively engaged—exactly what a company needs in workers who will contribute to profits -> correct