Answer: b. DNA
Explanation:
DNA is a genetic material commonly found in all living beings. It is present in a thread like structure that is called as the chromosome. The DNA is double helical structure which exhibits the segments of small units called as the genes. The gene is a hereditary material which encodes for a particular protein. Each gene is responsible for determining a particular trait in living beings.
Some are, depression, anxiety, irritability. hope this helps
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