Bacterial disease are controlled by use of chemicals

Answer: Option C

Bacterial diseases are controlled by the use of chemicals called Antibiotics.
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of such infections.
They may either kill or inhibit the growth of bacteria. A limited number of antibiotics also possess antiprotozoal activity.