Which Approach Would Help to Identify Biologically Produced Sulfur in a Sediment

Question

Which approach would help to identify biologically produced sulfur in a sediment sample?
A) enrichment
B) isotopic fractionation
C) microautoradiography
D) microelectrodes

Accepted Answer

Isotopic fractionation can help to identify biologically produced sulfur in a sediment sample as microbes can selectively assimilate lighter isotopes of sulfur, leaving heavier isotopes behind. Therefore, the presence of a large isotopic fractionation can indicate biological activity. The other options listed (enrichment, microautoradiography, and microelectrodes) may be useful for other purposes, but are not specifically tailored to identifying biologically produced sulfur in sediments.