Magnetic Substances
Magnetic substances are materials that possess magnetic properties and can be attracted to a magnet or be magnetized themselves. These substances have the ability to create a magnetic field and interact with other magnetic materials.

Explanation
Among the given options, the substance that is not a magnetic substance is Silver.

Properties of Magnetic Substances
To understand why silver is not a magnetic substance, let's take a look at the properties of magnetic substances:

1. Ferromagnetism: Ferromagnetic materials are strongly attracted to magnets and can retain their magnetization even after the external magnetic field is removed. Examples of ferromagnetic substances include iron, nickel, and cobalt.

2. Paramagnetism: Paramagnetic materials are weakly attracted to magnets and their magnetic properties are temporary. They only exhibit magnetic behavior in the presence of an external magnetic field. Examples of paramagnetic substances include aluminum, platinum, and oxygen.

3. Diamagnetism: Diamagnetic materials are weakly repelled by magnets and exhibit no permanent magnetic properties. They have a slight negative magnetic susceptibility. Examples of diamagnetic substances include copper, silver, and gold.

Silver as a Diamagnetic Substance
Silver is classified as a diamagnetic substance. Diamagnetic materials have a weak, negative magnetic susceptibility, meaning they are repelled by magnets. When a diamagnetic substance is exposed to a magnetic field, it generates a weak magnetic field in the opposite direction, causing repulsion.

Therefore, silver does not possess the ability to be attracted to magnets or retain magnetization. It lacks the necessary atomic and electronic structure to exhibit magnetic behavior.