Can Astronomers Observe Nebulae, the Regions Where Stars Form

Can astronomers observe nebulae, the regions where stars form?

A) Yes. A number of them can be seen easily with low-power binoculars.
B) Yes, but a medium-size telescope (say, 16'') is required to see any of them.
C) Yes, but only a powerful research instrument can see them.
D) No. Nebulae are very short-lived phenomena. They either collapse to form star systems, or they disperse. Theoretically, it is known they exist for short periods of time, but astronomers have never observed any of them directly.