A Box Is on a Scale

Multiple Choice

A box is on a scale.In which of these situations will the scale reading NOT equal the weight of the box?

A) The scale and box are in an airplane flying at constant speed.
B) The scale and box are in an elevator rising at constant speed.
C) The scale and box are in a hot air balloon in level flight.
D) The scale and box are on a steep slope, held in place by friction.
E) The scale and box are on Mars.