Matter can recycle through the biosphere because -

Matter can cycle through the biosphere because biological systems do not use up matter, they transform it. The matter is assembled into living tissue or passed out of the body as waste products. ... Simply put, biogeochemical cycles pass the same molecules around again and again within the biosphere.

Explanation:

answer a

prokaryotic cells do not have a nucleus in which the dna is stored in, it floats freely inside the cell.

eukaryote cells do have a nucleus in which the dna is stored in.

the real answer is b. scintillation counter