In Connection with a Star, What Does the Phrase "Metal-Poor

In connection with a star, what does the phrase "metal-poor" mean?

A) The star has a low abundance of all elements heavier than hydrogen in its spectrum.
B) The star has a low abundance of all elements heavier than hydrogen and helium in its spectrum.
C) The star has a low abundance of all elements in its spectrum.
D) The star might or might not have a low abundance of carbon in its spectrum but is definitely weak in iron.