The correct option is D D. Tropic of Cancer
78. D
On 21st June, the northern hemisphere is tilted towards the sun. The rays of the sun fall directly on the Tropic of Cancer. As a result, these areas receive more heat. Since a large portion of the northern hemisphere is getting light from the sun, it is summer in the regions north of the equator. The longest day and the shortest night at these places occur on 21st June. This position of the earth is called the summer solstice.