Was not a successor to william the conqueror.
a. simon de montfort
c. henry i
b. king john
d. henry ii
select the best answer from the choices provided

The answer is D. Henry II

Henry II of England is the Successor of Geoffrey of Anjou. during his Era, Henry II of England managed to conquer Ireland, Wales, Scottland, and Brittany.

Henry's empire quickly fall during the reign of His incompetent youngest Son, John.

The person who wasn't a successor to William the Conqueror would be Henry II - D.

Namely, when we're talking about William the Conqueror and his successors, we're talking about the English kingdom and kings or monarchs who were English kings later one. From the list you've provided - Henry II wasn't one. 

Provide more information so i can answer your question; )