$A$ scientist associated with the discovery of the first 'antibiotic' is

In $E. coli$,when the flagella rotate in a clockwise and anticlockwise direction,the movements are:

Antibiotics are mostly obtained from

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?

Select the appropriate option for $Saccharomyces \ cerevisiae$.

What do photosynthetic microbes produce?