Consider the Chemical Reactions of the Sulfur Cycle Shown in Figure

Multiple Choice

Consider the chemical reactions of the sulfur cycle shown in Figure 26.10. Oceans constitute the most significant reservoir of sulfur in the biosphere, and sulfate (SO₄^2-) reduction is the predominant form of anaerobic respiration in marine environments. In such cases, oxidized sulfur compounds like SO₄^2- are the electron acceptors instead of what?

A) water
B) oxygen
C) hydrogen
D) carbon dioxide