The cost, in dollars, of printing n digital photos is f(n) = 1.50 + 0.20n. Which statement is correct?

A. For each additional photo printed, the cost increases by $1.70
B. For each additional photo printed, the cost increases by $1.50
C. For each additional photo printed, the cost increases by $0.20
D. For each additional photo printed, the cost increases by $1.30