I need help thank you

B

Explanation:

A solar system is just a few planets which are smaller than nebulae or galaxies.

Nebulae is pretty much a cloud of dust and gas but it's still smaller than a galaxy

And then the universe kind of includes everything so there's nothing bigger than that

the element that provides strength to the exoskeletons of clams and oysters is phosphorus. this is so because calcium carbonate is the main component in the shells.

explanation:

c.) polymerase chain reaction

- "unlike the original dna fingerprinting method, dna profiling does not use restriction enzymes to cut the dna. instead it uses the polymerase chain reaction (pcr)? to produce many copies of specific str sequences. pcr is an automated procedure that generates lots of copies of a specific sequence of dna."