If our year were twice as long (that is, if earth took twice as many days to complete each orbit around the sun), but earth's rotation period and axis tilt were unchanged, then

the four seasons would each be twice as long as they are now

Explanation:

A year is the result of the Earths revolution around the sun i.e., the Earth takes 365 days to complete one revolution around the sun. A day is the result of the Earth's rotation on its axis i.e., it takes 24 hours for Earth to complete one rotation on its axis.

The Earth is titled by about 23.5 degrees, this results in the seasons of Earth. The distance from the sun has nothing to do with the seasons. During the northern hemisphere winter the Earth is actually closer to the sun than in the summer. So, if our year was twice as long then the seasons would be twice as long.

i guess it’s a and b

it has to be b, about 97 percent.