Which of the following sentences uses commas correctly?
A.
For the past two years Frank has played basketball, for the YMCA's 12 and under league.
B.
For the past two years Frank has played basketball for the YMCA's 12 and under league.
C.
For the past two years, Frank has played basketball, for the YMCA's 12 and under league.
D.
For the past two years, Frank has played basketball for the YMCA's 12 and under league.