A. clarity
B. certainty
C. rationality
D. perversity
Solution:
ambiguity : the quality of being open to more than one interpretation.
clarity : the quality of being certain or definite.
certainty : firm conviction that something is the case.
rationality : the quality of being based on or in accordance with reason or logic.
perversity : a deliberate desire to behave in an unreasonable or unacceptable way; contrariness.
Antonym of ambiguity is clarity