Find the term that does NOT fit into the below series:F - 6, I - 9, L - 11, O - 15, R - 18, U - 21, X - 24

Find the term that does NOT fit into the below series:F - 6, I - 9, L

1.	Find the term that does NOT fit into the below series:F - 6, I - 9, L - 11, O - 15, R - 18, U - 21, X - 24
A.	U-21
B.	O-15
C.	L-11
D.	R-18
Answer» D. R-18