The image formed by a convex spherical mirror will always be
a. inverted and larger than the object.
b. upright and larger than the object.
c. inverted and smaller than the object.
d. upright and smaller than the object.

a. inverted and larger than the object.

A mirror is used to see your own reflection. Earlier in the days, people would use a still water to see their reflection. It is basically used for grooming. Spherical mirrors have been used by earlier mathematicians and physicist to conduct experiments related to geometry. 

An atom's smaller negative particles are at a distance from the central positive particles, so the negative particles are easier to move.