Gnomon is a part of _________. 

Solar clock

The correct answer is option 1. Solar clock.

Gnomon is a part of Solar clock.

A gnomon is the part of a sundial that casts the shadow used to indicate the time. Sundials, also known as solar clocks, use the position of the Sun and the shadow cast by the gnomon to tell time. The shadow moves in a predictable manner throughout the day, allowing people to determine the time based on the position of the shadow relative to hour markers on the sundial. Therefore, a gnomon is an essential component of a solar clock or sundial.