(A) Singlet carbenes have opposite spin (antiparallel).
(R) They have a bent structure.
A. If both (A) and (R) are correct and (R) is the correct explanation of (A).
B. If both (A) and (R) are correct but (R) is not the correct explanation of (A).
C. If (A) is correct but (R) is incorrect.
D. IF (A) is incorrect but (R) is correct.