The size relationship between different objects, in a scene or between parts of the same object, are initially determined by the position of the camera, not the choice of lens. The only aspect of perspective that the lens determines is the angle of the view or how much is included in the frame.  The shorter the lens, the wider the angle of view, which means more of the scene will be recorded on the film.  The longer the lens, the narrower the angle of view and a smaller section of the scene will be recorded.  By standing in the same place with lenses of different focal lengths, the same photograph can be obtained simply by enlarging a section of the photograph made by the shorter lens and the perspective is relatively the same.
 
 

SHAPE AND DISTORTION CONTROL

The size of the subject is determined by the projection distance between the lens and the film plane, which is a function of the camera-to-subject distance and the focal length of the lens.

The shape of the subject and the size relationships between different objects in the scene are also determined by the lens-to-film plane projection distances.