Which statement is true about oxygen and rocks? both are mixtures. both are pure substances. oxygen is a mixture and a rock is a pure substance. oxygen is a pure substance and rocks are mixtures.

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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