Answer: A
Explanation: Lethargic ( to be sluggish/ apathic) to energy ( movement or strength to do something)
All the sentences make sense and have no missing pronoun
In A,it refers to the paint
In B,it refers to the fish
In C,it refers to the first song
So,all are correct
6 this is because 3 waves have spread out and 3 waves are together