Monascus purpureus is commercially used in the production of which of the following?

Blood cholesterol-lowering agent, statins

The correct answer is Option (4)- Blood cholesterol-lowering agent, statins

Statins produced by the yeast Monascus purpureus have been commercialised as blood-cholesterol lowering agents. It acts by competitively inhibiting the enzyme responsible for synthesis of cholesterol.

Microbes especially yeasts have been used from time immemorial for the production of beverages like wine, beer, whisky, brandy or rum. For this purpose the yeast Saccharomyces cerevisiae  is used for fermenting malted cereals and fruit juices, to produce ethanol.

Streptokinase, produced by the bacterium Streptococcus and genetically modified, serves as a "clot buster" in the removal of blood clots from the vessels of individuals who have experienced a heart attack.

Microbes are also used for commercial and industrial production of certain chemicals like organic acids, alcohols and enzymes. Examples of acid producers are Aspergillus niger (a fungus) of citric acid.