The end product of carbohydrate metabolism is-
A. $CO_2$ and $H_2O$
B. $NH_3$ and $CO_2$
C. $NH_3$ and $H_2O$
D. $CO_2$

Hint: Carbohydrates are the fibers, sugars, and starches that are present in milk products, vegetables, grains, and fruits. The primary function of carbohydrate is to store energy, spare proteins, build macromolecules, and provide energy. Glucose is an important carbohydrate that gets broken through the glycolysis cycle and then it enters the other cycles to generate energy.

Complete answer:
The carbohydrates are a type of biomolecule that consists of oxygen, hydrogen, and carbon molecules. The ratio of oxygen and hydrogen is 2 is to 1. It is highly classified as a type of aldehyde. The carbohydrate metabolism is an entire biochemical process that is responsible for interconversion, breakdown, formation and metabolic formation of carbohydrates.

The end product of a carbohydrate metabolism will be $CO_2$ and $H_2O$ because the carbohydrates constitute the carbon, hydrogen and oxygen molecule, in their empirical formulas.

Hence, the correct answer is option (A).

Additional information:
• The carbohydrates do not consist of ammonia in their end product because nitrogen is not used as the initial product. Thus, option [B] and option [C] both are incorrect.
• The carbohydrate also has water as its constituent in the bio molecular chain, or in simple words hydrogen molecule is also present as an initial product. So, water must come as the end product. Thus, option [D] is incorrect.

Note: The aldehyde is a group that is present in the chemical classification system. This group mainly consists of a bound among the carbon, hydrogen, and oxygen. And aldehydes are present on the terminal carbon group of the whole carbon chain.