Which one of the following is a biconditional?

Question

A.

B.

C.

D.

Answer 1

A. A biconditional is a proposition of the form "IF and Only IF P, Then Q"

it combines "If P then Q" with "If Q then P" so the arrow runs in both directions.

in A, ~(PvQ) is equivalent to P above, and r is equivalent to Q