If Max and Matt Are Identical Twins and You Know

If Max and Matt are identical twins and you know that Max has a psychological disorder,what can you say about Matt?

A) Matt will definitely have the disorder as well.
B) Matt has the same probability of having the disorder as the normal population.
C) Matt has a greater likelihood of having the disorder than the normal population, but less than he would if he were a dizygotic twin.
D) Matt is as likely to have the disorder as he would be if he was a non-twin sibling of Max.