Respuesta :
Answer: Option B
Explanation:
A chemist is performing an experiment in which he is testing the effect of various phosphorus concentration on the growth of plants.
She decides to change the concentration of phosphorus on every 5th day over a total growth period of 20 days.
The growth of plants will change according to change in concentration of phosphorus. So, the concentration of phosphorus is independent variable.
Hence, the correct answer is option B