Factor Out the Largest Possible Common Factor $$60 \mathrm { x } + 20$$

Factor out the largest possible common factor.
- $$60 \mathrm { x } + 20$$

A) $20 ( 3 x + 1 )$
B) $20 ( 3 x )$
C) $4 ( 15 x + 5 )$
D) $5 ( 12 x + 4 )$