Which of the Following Statements About Photochemical Electrocyclic Reactions Is

Multiple Choice

Which of the following statements about photochemical electrocyclic reactions is not true?

A) In photochemical reactions,we consider the orbitals of the HOMO of the excited state to determine the course of the reaction.
B) Photochemical electrocyclic reactions occur in a conrotatory fashion for a conjugated polyene with an odd number of p bonds.
C) Photochemical electrocyclic reactions occur in a disrotatory fashion for a conjugated polyene with an even number of p bonds.
D) In photochemical reactions,we consider the orbitals of the LUMO of the excited state to determine the course of the reaction.