A child is standing on a set of bathroom scales in a lift (an elevator) measuring his mass. The mass which he reads on the scales is M whilst the lift is stationary. When the lift descends at a constant speed, which of the following statement is not correct?
A. His mass remains the same
B. His weight remains the same
C. The reading on the scales depends on the speed of the lift
D. The reading on the scales remains the same