Function f(x) is positive, increasing and concave down on the closed interval [a, b]. The interval [a, b] is partitioned into 4 equal intervals and these are used to compute the left sum, right sum, and trapezoidal rule approximations for the value of the integral from a to b of f of x dx. Which one of the following statements is true

A. Trapezoidal rule value < Left sum < Right sum
B. Left sum < Trapezoidal rule value < Right sum
C. Right sum < Trapezoidal rule value < Left sum
D. Cannot be determined without the x‐values for the partitions