Consider a specific point on the surface of the earth (say, the city of Delhi). The temperature at a given time of day (say, 12.00 noon) will in general be higher in summer than in winter. This is because.

Answer: (b) sunrays falling on the earth are inclined more towards the surface of the earth in winter

In winter the rays strike at a low angle and spread over more area, so they heat less.

The idea

The same sunlight heats more strongly when it falls on a smaller surface area. A higher noon Sun gives more direct rays, and longer days add more heating. Earth’s axial tilt makes these conditions alternate between hemispheres through the year.

Northern hemisphere tilts towards the Sun → Noon Sun rises higher in the sky → Rays fall more directly → Energy is concentrated on a smaller area → Daylight lasts longer → Daily heating increases

Why the others are wrong

(a) Earth is farthest from the Sun in July (northern summer) — distance is not the reason.

(c) Not relevant.

(d) In winter the northern axis tilts AWAY from the Sun.

The trap

The “closer in summer” idea is a classic misconception.

Elimination technique

January perihelion occurs during northern winter, so the closer-in-summer claim fails. The northern axis also leans away from the Sun in winter; the useful remaining cause is the angle of the rays.

Also know

Earth is nearest the Sun at perihelion in early January and farthest at aphelion in early July. Both hemispheres share this distance change, yet have opposite seasons, which shows why distance is not the main seasonal cause. Slanting rays also travel through a longer atmospheric path.