Which of the following statements is false regarding microorganisms?

Antibiotics are primarily obtained from which of the following sources?

Mushrooms are a rich source of . . . . . . .

On which bacteria was Alexander Fleming working during the discovery of penicillin?

The oldest cultivated organism,yeast,was discovered by:

Identify the correct statements from the following:
$(A)$ Microbes have been used for centuries.
$(B)$ Not all microbes are pathogenic.
$(C)$ There are various methods to culture microbes in a nutrient medium.
$(D)$ Fungi,Cycas,viruses,and bacteria are examples of microbes.