Antonio observes the weather one afternoon. He claims that thunderstorms are likely. Which observation provides evidence that supports this claim? There is a light wind. The temperature is 23 °C (75 °F). The winds are blowing from the east. The clouds are mainly cumulonimbus.

The clouds are mainly cumulonimbus.

Explanation:

A Thunderstorms is a relatively small storm but usually quite intense. As little as 10 percent of thunderstorms may be considered severe globally. These severe thunderstorms may lead to high winds, hail, flash floods, and tornadoes. Severe thunderstorms may be injurious to health and even lead to fatalities.

Thunderstorms are produced by cumulonimbus clouds, hence Antonio's observation of a cumulonimbus correlates well with the prediction of a thunderstorm.