Answer: ,Option B.
The Earth's axis has a 23.5 degree tilt.
Explanation:
The Earth axis of rotation is tilted to 23.5 degrees which is relatively to the orbital plane, this lead to differences in seasons of the places on Earth at a particular time. The angles varies overtime but moon gravitational pull prevent it from shifting more than a degree. There is different in seasons in the northern and southern hemisphere because at a time one part of it exposed to the Ray's of sunlight than the other which lead how the Earth's revolve round it's axis.
Answer: it shortened the name and easier to remember
Explanation:
Because there are too many sex chromosomes I think
A nucleotide is DNA
(Also RNA)
Hope that helped! :)