If the alternatives are mutually exclusive and the MARR is 15% per year, the alternative to select is

Only Alternative B

Explanation:

As the alternatives are mutually exclusive, the alternative to select would be the one that is superior to all of the others and above MARR.

B, C and D all have rates of return higher than MARR so they will pass the first step.

When C is compared to B, it has an incremental return of 10% which is less than the MARR so C will be discarded as B is a better option.

Now compare B with D. When D is compared to B, it has an incremental return of 13% which is less than the MARR so B is again superior.

Alternative B should therefore be chosen as it is better than the other options.