Answer: Only Alternative B
Step-by-step 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.