You will be given a trivia clue, and the category it belongs to. You should answer with the best answer that belongs in the category and is described by the clue. For simplicity, answers should be in all lower cased letters.

Category: BASEBALL NICKNAMES 
Clue: Hall of Famer "Eck"
dennis eckersley

Category: GLAND FINALE 
Clue: This human gland important in the immune system takes its name in part from its resemblance to an herb
the thymus gland

Category: TRY "TRI" AGAIN 
Clue: It straightens the arm at the elbow

the triceps