Does the lens on every camera control the depth of field and light?

this is a question on my comm tech exam -_-;; plz help

Actually only in conjunction with the shutter. ~
And the shutter does most of the controlling.

Not the lense, the aperture. The size of the hole which admits light to the lense. Large hole eg. f1.8 = shallow depth of field. Small hole, eg. f 8 = deep depth of field. Also, a large aperture opening will let in more light.

the depth of field is controled by aperature and shutter speed. The aperature is within the lens and the shutter is a part of the camera body.

These really aren't questions are they?

The questions sound as if they were written by someone who is NOT a photographer, but was assigned to write the test anyway.

Yes - The DOF is controlled by the aperture. The larger the #, the smaller the opening, the greater DOF and vice versa. The opening also affects the amount of light that is let in. Shutter speed does the same for the light only, but also affects the motion captured. If you wanted stop action or a little blur.

F/22 aperture will give more depth of field,f/1.8 aperture will give lesser depth of field.