Find the missing number?

Answer: Option B

First Circle:
Multiplication of to upper numbers /2 = Lower number.
= (8 * 4)/2 = 16.

Second Circle:
Multiplication of to upper numbers /3 = Lower number.
= (8 * 9)/3 = 24.

Third Circle:
Multiplication of to upper numbers /4 = Lower number.
= (12 * 9)/4 = 27.
Missing Number = 27.