I believe that it is B chemicals containing carbon
A chemical reaction is going to be your answer
Answer: The moles of melatonin are 0.000043
Explanation:
According to avogadro's law, 1 mole of every substance weighs equal to its molecular mass and contains avogadro's number
of particles.
To calculate the moles, we use the equation:

Given mass of melatonin = 0.01 g
Molar mass of melatonin
= 232.28 g/mol

Thus the moles of melatonin in 0.01 g are 0.000043