Final answer:
Viscosity is a fluid's resistance to flow and depends on its intermolecular forces. Viscous materials, which have strong intermolecular forces, flow slowly. The correct answer is b) Flows slowly.
Step-by-step explanation:
Viscosity is a measure of a fluid's resistance to flow. A material that is viscous flows slowly. This property is influenced by the intermolecular forces within the fluid; stronger intermolecular forces result in a higher viscosity. Liquids like water and gasoline with lower intermolecular forces flow more freely and are considered to have a low viscosity, whereas substances like motor oil, molasses, and syrup flow slowly due to higher intermolecular forces, hence they are more viscous. Viscosity can be measured using the time taken for a quantity of liquid to travel through a narrow tube or how fast steel balls fall through the liquid. The unit of viscosity is the poise (mPa.s); the larger the value, the greater the viscosity.
Therefore, the correct answer to the student's question is: A material that is viscous b) Flows slowly.