A solid, liquid, and gas can exist together at the

(A) sublimation point
(B) triple point
(C) boiling point
(D) freezing point
(E) melting point

2019 U.S. National Chemistry Olympiad Local Section Exam Question 20

Which sample has the greatest entropy at a given temperature?

(A) 2 mol HBr(s)
(B) 2 mol HBr(l)
(C) 2 mol HBr(g)
(D)  1 mol H2(g) + 1 mol Br2(l)