Which of the Following Statements Concerning Electrocyclic Reactions Is Correct

Multiple Choice

Which of the following statements concerning electrocyclic reactions is correct?

A) The ground state HOMO of a compound with an even number of conjugated double bonds is asymmetric.
B) The allowed mode of ring closure under thermal conditions for a molecule containing an even number of conjugated double bonds is disrotatory.
C) The allowed mode of ring closure under photochemical conditions for a molecule containing an odd number of conjugated double bonds is disrotatory.
D) both B and C
E) none of the above