Identify the odd one out.

Medicines are either man-made (i.e.,synthetic) or obtained from living organisms like plants,bacteria,animals,etc.,and hence,the latter are called natural products. Sometimes,natural products are chemically altered by man to reduce toxicity or side effects. Write against each of the following whether they were initially obtained as a natural product or as a synthetic chemical: $(a)$ Penicillin $(b)$ Sulphonamide $(c)$ Vitamin-$C$ $(d)$ Growth hormone.

The oldest cultivated organism,yeast,was discovered by:

Who was the first discoverer of the antibiotic penicillin?

Consider the following statements $(A-D)$ about organic farming.
$(A)$ Utilizes genetically modified crops like Bt cotton
$(B)$ Uses only naturally produced inputs like compost
$(C)$ Does not use pesticides and urea
$(D)$ Produces vegetables rich in vitamins and minerals
Which of the above statements are correct?

What do photosynthetic microbes produce?