answer= D: 10/24 and 9/24
step-by-step
1. find a common denominator
2. 12 and 8 dont share common denominators or 12 and 16 so you can cross off A and B.
3. rename 5/12 with a denominator of 24 then do the same with 3/8
4. 5/12 will turn into 10/24 and 3/8 will turn into 9/24
5. your answer is then D