Definition: This is two or more elements chemically combined in a fixed ratio.

Compound

Explanation:

Compounds – Compounds are chemical substances made up of two or more elements that are chemically bound together in a fixed ratio.

Example of compounds includes water (H2O), Hydrogen Peroxide (H2O2), etc. You could see water’s chemical formula, it says it has 2 atoms of Hydrogen combined with 1 atom of oxygen and in hydrogen peroxide, it has 2 atoms of hydrogen and two atoms of oxygen.

the leaf is an organ of a typical plant, and the main functions are to complete photosynthesis and allow the plant to exchange gas, just like how we have the respiratory system. leaves have the stomata, which collects maintains co2 and o2 levels. this is necessary for cell metabolism. the leaf also collects sunlight using chloroplasts. succinctly, leaves own a pivotal role in sustaining plant life.

b is the correct answer

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