Correct Answer - B
If the object is placed at a distance `u_(0)` from the lens, the angel subtended by the object on the lens is `beta = (h)/(u_(0))` where h is the height of the object. The maximum angle subtended on the unaided eye is `alpha = (h)/(D)`
Thus, the angular magnification is
`m = (beta)/(alpha) = (D)/(u_(0)) = (25 cm)/(3.6 cm) = 7.0`