Question

As opposed to concave lenses, which characteristic of convex lenses makes them useful in microscopes?

Convex lenses can produce images larger than objects.
Convex lenses can produce upright images.
Convex lenses cause light rays to spread out.
Convex lenses cause light rays to refract.

Answer 1

Convex lenses can produce images larger than objects.

They converge light to form magnified images (which is why converging lenses are used in the objective and eyepiece of microscopes).