The volume of an embankment having a total length of L and cross section areas of four sections at an interval of H are $$A_1, A_2, A_3, A_4$$ using the trapezoidal method is

A

$$H\left[\frac{(A_1 + A_4)}{2 + A_2 + A_3}\right]$$

B

$$H\left[\frac{(A_1 + A_4)}{4 + A_2 + A_3}\right]$$

C

$$L\left[\frac{(A_1 + A_4)}{2 + A_2 + A_3}\right]$$

D

$$\frac{L}{3}\left[(A_1 + A_4) + 2(A_2 + A_3)\right]$$