Final answer:
Methionine is an essential amino acid that is absent or limiting in beans.
Step-by-step explanation:
Methionine is an example of an essential amino acid (AA) as it cannot be synthesized by the body and must be obtained from the diet.
This essential AA is absent or limiting in beans. Beans are a good source of protein but do not contain all the essential AAs in sufficient quantities.
Therefore, the correct answer is C. Methionine.
Learn more about essential amino acid