What was Euclid's contribution to mathematics that's still in use today?

Question

A. his system of logic
B. his measurement of the size of the earth
C. his textbook The Elements
D. His design of the sun-centered solar system

Answer 1

C. his textbook The Elements

Euclid's "The Elements" is one of the most influential works in the history of mathematics. It systematically compiled and organized the knowledge of geometry of his time and introduced axiomatic methods, which are still a fundamental part of modern mathematics education.