Answer: <u><em>D. An observation that has a number associated with it</em></u>
Explanation: The answer is D. An observation that has a number associated with it. I would explain further, but it is pretty self explanatory.
<em>Good luck!</em>
MRNA is needed in the cells because it directs the synthesis of proteins which is found in the cytoplasm. It is a molecule that carries the message contained within DNA to the ribosome. The Proteins are assembled on the ribosomes using the mRNA nucleotide sequence as a guide.