An Astronomer Measures the Spectra of Two Stars,A and B

Multiple Choice

An astronomer measures the spectra of two stars,A and B.She finds that star A is nine times more luminous than star B and is three times as hot.How are their surface areas related?

A) Star A's area is three times larger than star B's.
B) Star A's area is two times larger than star B's.
C) Star A's area is the same size as star B's.
D) Star A's area is three times smaller than star B's.