If his hair is 14 cm long and hair grows approximately 1.3 cm per month, will there still be evidence of drug use in his hair?

it is possible since hair doesn't readily decompose. If the rate of hair growth is 1.3 cm per month and his hair is 14 cm long, then it means that the test can still trace a drug that was ingested 11 months ago

answer:

c it's motivated by the needs of the patient.