GENERAL KNOWLEDGE

Detailed explanation-1: -Most Diffuse nebula contain mostly hydrogen with smaller amounts of helium, oxygen, sulfur, and other heavier elements. Eventually, when the stars born from the nebula progress, their solar wind will blow away the nebula into space leaving almost nothing but an open cluster of stars.

Detailed explanation-2: -By examining the spectra of nebulae, astronomers infer their chemical content. Most emission nebulae are about 90% hydrogen, with the remaining helium, oxygen, nitrogen, and other elements.