Which placement of grouping symbols in the expression gives it a value of 6?

7 • 5 – 4 • 5 + 9

A.
7 • (5 – 4) • (5 + 9)

B.
7 • [(5 – 4) • 5] + 9

C.
7 • [5 – (4 • 5) + 9]

D.
(7 • 5) – [(4 • 5) + 9]