Physics help

Question

Which of the following are true about a planet when it is at its greatest distance from the Sun?
A. It is at aphelion.
B. It is at perihelion.
C. It is moving at its greatest speed.
D. It is moving at its slowest speed.

Answer 1

At its greatest distance, it is at aphelion, and moving the slowest (whereas at its closest distance, it is at perihelion, and moving the fastest).  Answers (A) and (D) are correct.

Answer 2

Aphelion is when a planet is furthest from the sun.  Perihelion is when it's closest.  The closer a planet is to the sun, the faster it moves.