Answer:
The answer is letter b, mixture.
Step-by-step explanation:
Let's define what a mixture is at first.
Mixture- In Chemistry, mixture is a material made up of two or more different substances that are physically combined. The identities of the substances are retained. There are two types of mixture: homogenous and heterogenous.
Homogenous mixture examples: saline solution and air.
Heterogenous mixture examples: sand and oil and water.
The student's record shows the color of the substance as yellow, shiny powder. It could mean that the substance is a mixture of different kinds of powders. This is already a hint, since powder is a form of mixture. The record also shows that the substance is attracted to magnet. Part of the powder mixture contains something that is attracted to magnet. It could be an iron powder, which is the shiny one. The substance can then be classified as letter b, mixture.