You are given the following pieces of information: ∫¹⁸₁₁​f(x) dx=−32, ∫¹⁸₁₃f(x) dx=−14, ∫₁₆¹¹​f(x) dx=47. What is the value of ∫¹⁸₁₆f(x) dx?
a) 79
b) 61
c) 47
d) 15