Question

what type of solar activity is an arc of gas that gets ejected from the chromosphere?
coronal mass ejection
solar flare
solar prominence
coronal hole

Explanation:

A solar prominence is an arc - like structure of gas that extends from the Sun's chromosphere. Coronal mass ejections are large expulsions of plasma and magnetic field from the Sun's corona. A solar flare is a sudden flash of increased brightness on the Sun. A coronal hole is a region of the Sun's corona that is cooler and has lower - density plasma.

Answer:

solar prominence