Final answer:
Cirrus clouds, which are high in the atmosphere and made up of ice crystals, are the type of cloud that produces a halo.
Step-by-step explanation:
The type of clouds that produces a halo are A) Cirrus clouds. These clouds are high in the atmosphere and are primarily made up of ice crystals. When light is refracted, or bent, by these ice crystals, it often results in the visible phenomenon known as a halo. This is different from other cloud types such as B) Cumulus clouds, C) Stratus clouds, and D) Nimbostratus clouds, which generally do not create this effect.
Learn more about Cirrus clouds