Why Are Carbonaceous Chondrites Thought to Be Original Material That

Why are carbonaceous chondrites thought to be original material that formed in the early solar nebula?

A) Carbonaceous chondrites show a Widmanstätten pattern, which indicates slow condensation from gaseous material.
B) The minerals of a carbonaceous chondrite contain up to 20% water, which would have evaporated away if the chondrite had been strongly heated.
C) Carbonaceous chondrites consist mostly of carbon, which was the dominant substance condensing in the outer solar nebula.
D) Carbonaceous chondrites consist almost entirely of ice, which would have sublimed away by now if this were not the first time the chondrite was passing close to the Sun.