(Figure: Production Possibilities) Which Statement Is NOT Correct Regarding Point

(Figure: Production Possibilities) Which statement is NOT correct regarding point X?

A) The combination produced at point X is productively efficient.
B) Society might prefer other combinations on the line to the mix of output a point X.
C) Because it is on the line, combination at point X has no opportunity cost.
D) The combination of output at point X might not be allocatively efficient.