Final answer:
A highly opaque material absorbs most light and allows negligible light to be transmitted or reflected. Reflective surfaces, like mirrors, still absorb a small percentage of light, whereas opaque materials do not transmit light effectively.
Step-by-step explanation:
When a material is highly opaque, it absorbs most light. This is due to the fact that opaque materials do not allow light to pass through them. Instead, they capture the energy of the light waves that strike them. For example, an ideal blackbody is a perfect absorber, which more closely models absorptive surfaces rather than reflective surfaces in terms of its interaction with light.
Reflective materials, such as a good-quality mirror, can reflect more than 90% of the light but still absorb some. Total reflection is a special case where light is entirely reflected, such as in certain angles with the phenomenon of refraction. Opaque materials are essentially the antithesis of this, as they allow negligible light to be transmitted or reflected, absorbing the majority of it instead.