Which of the following reaction (s) can generate a five membered ring as the major product?

Step-by-step solution

I ₂ will attack the double bond to form a cyclic halonium ion. It then undergoes on intramolecular reaction. Formation of five membered ring is favoured because (i) attack by a nucleophile on a halonium ion normally takes place at the more substituted site. (ii) Formation of five membered ring is more probable.