The water of the holy Ganga river is considered pure due to the presence of:

Which is the first discovered antibiotic?

What do photosynthetic microorganisms produce?

Consider the following statements:
$I.$ Antibiotics are chemical substances produced by some microorganisms which can kill or retard the growth of other disease-causing microorganisms.
$II.$ Penicillin is the first antibiotic discovered by Alexander Fleming $(1928)$,while working on the bacterium $Staphylococcus$ $aureus$.
$III.$ The function of penicillin as an antibiotic was established by Ernst Chain and Howard Florey.
Which of the statements given above are correct?

Who coined the term 'antibiotic'?

The term "antibiotic" was coined by