When an Allyl Cation Undergoes a Cycloaddition Under Photochemical Conditions

Multiple Choice

When an allyl cation undergoes a cycloaddition under photochemical conditions with ethylene (bonds forming at the ends of the π-systems) ,the cycloaddition is described as

A) [2+2] and suprafacial.
B) [2+4] and suprafacial.
C) [2+2] and antarafacial.
D) [2+4] and antarafacial.
E) [2+3] and antarafacial.