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.
