What is defined as how clear or sharp a particular image is? focus angle shot obscurity

I believe the correct answer is: focus.

The camera represents a light-tight box that is used to expose a photosensitive surface to light and in order to focus the light onto the surface, most cameras use a lens to direct the light. Focus is an optical device that consists of a curved material that allows light to pass through it and defines how clear or sharp a particular image would be.

true! hope i !