The other elements are <u>A. 10 oxygen and 20 hydrogen</u>.
<h2>Explanation:</h2>
Carbohydrates are generally hydrates of carbon. A molecule of carbohydrate is usually made of elements like carbon, hydrogen and oxygen. Hydrogen and oxygen are in a 2:1 ratio like they present in water.
The empirical formula of carbohydrate is , where m and n can be different. They can also be called as saccharides and often as sugar. They can either be a small molecule like glucose or large molecules like starch.