Planets Go Around the Sun in Elliptical Orbits

Multiple Choice

Planets go around the sun in elliptical orbits. The highly exaggerated diagram below shows a portion of such an orbit and the force on the planet at one position along that orbit. The planet is moving to the right. F_|| and are the components of the force parallel (tangential) and perpendicular (normal) to the orbit. The work they do is W_|| and . At the position shown

A) W_|| slows the planet down;
speeds it up.
B) W_|| slows the planet down;
does no work on it.
C) W_|| speeds the planet up;
does no work on it.
D) W_|| speeds the planet up;
slows it down.
E) W_|| does no work on it;
speeds the planet up.