Which element is the main component in most of the substances of protoplasm?

Which is the most appropriate option for organic compounds?

The major part of the dry weight of a living organism is made up of . . . . . . .

Approximately $93$% of cellular matter is composed of which elements?

Which atoms are primarily present in organic compounds?

When a living tissue is ground in trichloroacetic acid to form a slurry and filtered through cheesecloth or cotton,the $.....$ passes through the cheesecloth or cotton.