A photograph of a landscape is captured by a drone camera at a height of 18 km. The size of the camera film is 2 cm × 2 cm and the area of the

A photograph of a landscape is captured by a drone camera at a height of 18 km. The size of the camera film is 2 cm × 2 cm and the area of the landscape photographed is 400 km2 .The focal length of the lens in the drone camera is :

(1) 1.8 cm 

(2) 2.8 cm

(3) 2.5 cm 

(4) 0.9 cm                                                       (JEE-2025)