All of the Following Statements About the Sun's Corona Are

Multiple Choice

All of the following statements about the Sun's corona are true.Which one explains why it is a source of X-rays?

A) The temperature of the corona's gas is some 1 to 2 million Kelvin.
B) The corona lies above the visible surface of the Sun.
C) The corona's gas consists mostly of hydrogen and helium.
D) The corona's structure is largely shaped by magnetic fields.