Final answer:
Nitrogen and phosphorus are essential for the production of the nucleic acid DNA, as they are components of the nitrogenous bases and phosphate groups in the DNA structure, thus the correct answer to the student's question is option (a)..
Step-by-step explanation:
Nitrogen and phosphorus are both crucial elements for the production of nucleic acids in human cells. These nucleic acids include deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). DNA is particularly significant as it contains the genetic instructions used in the growth, development, functioning, and reproduction of all known living organisms and many viruses.
Nitrogen is a major component of the nitrogenous bases, which, along with a pentose sugar (deoxyribose in DNA) and a phosphate group, make up the nucleotides that form the DNA polymer. The phosphorus in these nucleotides is part of the phosphate group that forms the backbone of the DNA structure.
Therefore, nitrogen and phosphorus are both critical for the production of deoxyribonucleic acid (DNA), thus the correct answer to the student's question is option (a).