Please help asap! Correct answer gets brainliest

Answer: C - 35
Step-by-step explanation:
If the ratio is 3:5:2 and red books is 21, I believe the answer is C, 35 as 5 times 7 equals to 35.
Answer:
C (35)
Step-by-step explanation:
21 red
There are only 3 red which means you have to find out how you get 21
Find what numbers go with 3
3x7 is 21
mutiply yellow by 7 and get your answer (5x7)
35