Emission nebulae radiate mainly in the ultraviolet part of the electromagnetic spectrum.

true
false

False

Emission nebulae are mostly star clusters that are composed of gas and cosmic dust. They usually have a characteristic red color, due to the radiation of hydrogen in the red region of the electromagnetic spectrum, called hydrogen-alpha.

It should be noted that these regions with large amounts of gas composed mostly of ionized hydrogen, is due to the presence of sources of ultraviolet radiation (most of the time, stars) and dust.

However, its emission spectrum is from hydrogen radiation.

Jet streams are relatively narrow bands of strong wind in the upper levels of the atmosphere. the winds blow from west to east in jet streams but the flow often shifts to the north and south. jet streams follow the boundaries between hot and cold air. the earth's rotation is responsible for the jet stream as well.

Then the answer would be d then