The sequence of nucleotides in a messenger RNA molecule (mRNA) is determined by the sequence of nucleotides in a a transfer RNA (tRNA) molecule. b protein molecule. c polysaccharide molecule. d DNA molecule.

D-DNA molecule

Explanation:

The process of copying the sequence of  DNA nucleotide  sequences to the mRNA is called   Transcriptions. It  is the  first stage in gene expression   for protein synthesis, and it involves the unwinding of the DNA double strands  molecules  by enzyme DNA Helicase into two  free strands,(by melting the hydrogen bonds between organic  bases), a process   initiated by the binding of enzymes RNA Polymerase to  the promoter sites on the DNA  template; the alignment of the mRNA  nucleotides on the  single DNA template strands in 3'-5  direction; the formation of  hydrogen bonds between the organic bases  of the template DNA  and   that of the messenger RNA single strands,(  and phosphodiesterbonds  within RNA nucleotide ), to form DNA-RNA complex.

The copying is done in  complimentary anti parallel fashion;5'-3' prime. direction.

 The  hydrogen bonds, between the bases  DNA-RNA complexes breaks,and  the releases  the mRNA  which  exists through the nuclear pores.Thus  this leads to copying of the the coded messages as seqeunce of DNA , from the DNA to the mRNA for gene expressions.

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explanation: