Concept of sustainable agriculture lies in

$BHC $ and $DDT $ belong to which class of pesticides

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 ?

Kattha' is obtained from the heart wood of

Consider the following four statements $(A-D)$ and select the option which includes all the correct ones only.

$(A)$ Single cell Spirulina can produce large quantities of food rich in protein, minerals, vitamins, etc.

$(B)$ Body weight­wise the microorganism Methylophilus methylotrophus may be able to produce several times more proteins than the cows per day.

$(C)$ Common button mushrooms are a very rich source of vitamin $C$.

$(D)$ A rice variety has been developed which is very rich in calcium.

The chemical formula of ’paris green' is