Antibiotics have greatly improved our capacity to treat deadly diseases. How many of the following diseases can be treated with antibiotics?

Plague, whooping cough, common cold, polio, diphtheria, leprosy, flu

The correct option is A 4
Antibiotics are chemical compounds that are produced by some microbes and can be used to retard the growth or kill other microbes. It used in the medical field as drugs to treat pathogenic infections.

Antibiotics are generally used against bacterial infections. Of the above mentioned diseases, plague, whooping cough, diphtheria and leprosy are caused by bacteria. So, the correct option is (a).

Antibiotics are not effective in case of diseases caused by viruses like common cold, flu, polio, etc as viruses live inside the cells of its host and antibiotics are not able to target them.