The branch of science which deals with chemicals is called chemistry.
The correct answer is D.
The solution which has more than two components is called a mixture.
In the question, the rock is made up of many minerals and other elements. Hence, rock is considered a mixture. But in oxygen, all the molecule of oxygen is mixed together and form a homogenous mixture that has only one component that is oxygen.
Hence, the correct option is D that is Oxygen is a pure substance and rocks are mixtures.
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https://brainly.com/question/19200238
