I suggest that you should try C......
<span>tRNA - Transfer RNA: Brings amino acids to ribosomes during translation.
rRNA - Ribosomal RNA: With ribosomal proteins, makes up the ribosomes, the organelles that translate the mRNA.
<span>snRNA - Small nuclear RNA: With proteins, forms complexes that are used in RNA processing in Eukaryotas. (Not found in prokaryotes.)</span></span>
<span>vaccine
The wording given is pretty much the exact definition of a vaccine. The key to how a vaccine works is that it provides to the immune system, samples of the surface proteins of the infectious materials. With those samples available, the immune system is able to produce antibodies that react to those proteins.</span>