D. Dedicated in May 1922, the Lincoln memorial was built to honor Abraham Lincoln.
Explanation:
The only comma needed in this sentence is one at the end of the adverbial phrase <em>Dedicated in May 1922, </em>to separate this modifier from the main sentence. There is no need for a comma between the month and year in an expression like May 1922, and placing a comma between the subject (<em>the Lincoln Memorial</em>) and predicate (<em>was built...</em>) as in option B is also wrong.
