Summertime in the Northern Hemisphere Is When

Multiple Choice

Summertime in the northern hemisphere is when

A) sunlight heats the atmosphere more when passing through a longer path when the Sun is at an oblique angle.
B) the clearest skies occur because of climate changes, leading to greater surface heating of Earth.
C) Earth is closest to the Sun in its elliptical orbit.
D) sunlight falls more directly on this hemisphere, heating it more than average.