Penicillin was discovered while observing the inhibition of growth of which organism?

Which of the following is not a yeast?

The role of bacteria in the carbon cycle is:

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.

Who was the first discoverer of the antibiotic penicillin?

Antibiotics are