Citric acid is obtained from which fungus?

Assertion $A$: $Ernest \text{ Chain}$ and $Howard \text{ Florey}$ improved the production of penicillin.
Reason $R$: Penicillin was obtained from the fungus $Penicillium \text{ notatum}$.
Which option is correct for Assertion $A$ and Reason $R$?

Which raw material is used in the fermentation process of making beer?

Which of the following is used as an immunosuppressive agent?

Which organism is useful for producing a chemical that inhibits immunity during organ transplantation?

Which steroid is used for transformation?