In the problem solving process, the final step is to try to

a.

generate multiple solutions

b.

review your results

c.

decide on a solution

d.

evaluate your choices

The final steps is to review your results.

This means that you have to check if the results meet the original requirements or statements.

Ideally, you should try to solve the same problem by a second method, and/or you should substitute the results into the given relationships given in the problem statement to chek coherence of your results.

Then the answer is option b.