Answer:
A. The North Pole is tilted towards the sun
Step-by-step explanation:
In Northern Hemisphere's summer, the North Pole is tilted towards the sun.
That's why the days are longer and warmer. While it's summer in the North, it's winter in the South.
The other offered answers are wrong:
B. South Pole is tilted towards the sun. That's when it's winter in the Northern Hemisphere.
C. the sun's rays grow less direct. No, on the contrary, that's why we get warmth in summer.
D. The sun appears directly overhead. That's not possible at any time of the year in the Northern hemisphere, you have to be close to the Equator line for this to happen.