All the biological macromolecules contain carbon, hydrogen and oxygen. however, most do not contain nitrogen. the category that contains nitrogen are

Macromolecules are the substances that are essential for the life. There are four macromolecules required for the healthy growth and development. these four categories of the macromolecules are the proteins, carbohydrates, nucleic acids, and fats. Among these four categories of the macromolecules, the proteins are the only ones which contain nitrogen in them.

Hence, the correct answer is 'protein'.

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explanation:

image result for how many calories of energy will 20 grams of carbohydrates provide in one gram provides 4 calories

consuming the right balance of protein, carbohydrates and fat can you maintain a healthy weight and optimize your energy levels. protein and carbohydrates both contain 4 calories per gram, while fat provides 9 calories per gram.