Choose the Correct Answer from the List Below

Choose the correct answer from the list below. Not all of the answers will be used.
-Chlorophyll a contains a(n) ____________ ion in the center of the tetrapyrole.

A) 960 nm
B) magnesium
C) ATP synthase
D) chloroplasts
E) thylakoids
F) copper
G) β-carotene
H) 680 nm
I) FAD
J) chlorophyll a
K) ferredoxin b
L) resonance energy transfer