Answer
(a) mRNA
Work Step by Step
mRNA serves the exact function in the question. It is responsible for making a copy of the DNA sequence in the nucleus and then traveling to the cytoplasm to deliver the information in order to create proteins.
(b) is not the correct answer because the role of tRNA is to bind amino acids with their matching mRNA codons. (c) is not the correct answer because the function of rRNA is to associate with ribosomes to create the protein itself by providing the subunits. (d) is incorrect because the only RNA that goes into the nucleus to copy the DNA is mRNA, all other RNA types are located in the cytoplasm and have their own functions.