Final answer:
Silver is a pure substance, while cereal, jelly bean, and shampoo are mixtures.
Step-by-step explanation:
The pure substance among the given options is Silver. A pure substance is made up of only one type of particle and cannot be separated into its constituent elements by physical means. Silver is an element on the periodic table, and as such, it is a pure substance. Cereal, jelly bean, and shampoo are all mixtures composed of different substances.
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