Which of the following is a true statement (for people in the northern hemisphere)?
(a) during the night, all stars rise in the east and set in the west
(b) all stars are fixed in the sky and do not appear to rise and set at all.
(c) polaris does not rise nor set

Explanation:

In the northern hemisphere the star , located in the constellation of the Little Bear (Ursa Minor in latin) is the polar star (known as Polaris).

This is because this star is currently located very close to the Earth rotation axis. That is why when observing the sky in the north direction, being in the northern hemisphere, Polaris will seem immobile in the middle of the rest of the stars.

However, it is necessary to note that  will not always be the polar star, because each year the Earth's totation axis moves approximately one degree, which will cause another star ( ) to take the place of Polaris within many years.

d.) greenhouse gases

a. it led to stricter immigration laws.