Nếu \(\int\limits_1^2 {f\le...

Câu hỏi: Nếu \(\int\limits_1^2 {f\left( x \right){\rm{d}}x = 3} \), \(\int\limits_2^5 {f\left( x \right){\rm{d}}x = - 1} \) thì \(\int\limits_1^5 {f\left( x \right){\rm{d}}x\,} \) bằng

A. -2

B. 2

C. 3

D. 4