Astronomers Know What the Solar Interior Is Like by

Astronomers know what the solar interior is like by

A) observing the interior directly. By using the appropriate filters it is possible to reduce the bright glow of the Sun and to peer directly at the Sun's interior.
B) constructing a miniature Sun in the laboratory and extrapolating the results to the real Sun.
C) using locally tested physics combined with observations to build a mathematical model of what the Sun should be like in its interior.
D) sending probes directly into the Sun and sending back the information.