According to Rankines formula the minimum depth of foundation should be:

A

$$\frac{W}{P}\left(\frac{1 + \sin \theta}{1 - \sin \theta}\right)^2$$

B

$$\frac{P}{W}\left(\frac{1 - \sin \theta}{1 + \sin \theta}\right)^2$$

C

$$\frac{P}{W}\left(\frac{1 + \sin \theta}{1 - \sin \theta}\right)^2$$

D

None of these