Which of the Following Does NOT Represent a Biochemical Signature

Which of the following does NOT represent a biochemical signature of diet?

A) the ratio of nitrogen isotopes varying with the overall importance of seafood
B) different photosynthetic processes resulting in varying ratios of carbon
C) strontium and calcium ratios indicating relative importance of meat and plant foods
D) different chemical compositions resulting from photosynthesis in bones of human skeletons
E) unusually low concentrations of lead found in bones of those who drink wine that has been stored in lead containers