In this task, you are given a sentence. You are expected to recognize the name of any form of chemical substances. Although there might be several correct answers, you need to write one of them.

Example Input: Effects of folic acid deficiency and MTHFR C677T polymorphism on spontaneous and radiation-induced micronuclei in human lymphocytes.
Example Output: folic acid

Example Input: Vitamin E deficiency impairs the somatostatinergic receptor-effector system and leads to phosphotyrosine phosphatase overactivation and cell death in the rat hippocampus.
Example Output: phosphotyrosine

Example Input: Methylation-mediated silencing of genes is not altered by selenium treatment of prostate cancer cells.
Example Output:
selenium