Bioactive molecule, cyclosporin A, is produced by:

Trichoderma polysporum

The correct answer is Option (2) → Trichoderma polysporum    

Cyclosporin A is a bioactive molecule that is widely used as an immunosuppressive agent in organ transplant patients. It plays a crucial role in preventing organ rejection by suppressing the immune system's response to the transplanted organ. This important medication is derived from the fungus Trichoderma polysporum.

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, Acetobacter aceti (a bacterium) of acetic acid; Clostridium butylicum (a bacterium) of butyric acid. 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.