Riemann Sums Question 2

The graph of the function $f$ is shown above for $0\leq x \leq 2$ . Of the following, which has the least value?

\int\limits_1^2 f(x)  dx

Left Riemann sum approximation of

\int\limits_1^2 f(x)  dx

with 4 subintervals of equal length

Right Riemann sum approximation of

\int\limits_1^2 f(x)  dx

with 4 subintervals of equal length

Midpoint Riemann sum approximation of

\int\limits_1^2 f(x)  dx

with 4 subintervals of equal length