Lenses can be found in a variety of objects which example does not have a lens?

a.) diving mask
b.) smart phone
c.) electron microscope
d.) night vision goggles

The correct option is B). Smart phone.

Explanation:

Consider the provided options:

Diving masks and night vision goggles have a lens.

Electron microscopes have electromagnetic lenses or electron optical lens systems.

Which means diving mask, electron microscope and night vision goggles have a lens.

Thus, the correct option is B). Smart phone.