Non-coded RNA are small RNA molecule that cannot be translated by host machinery. They are useful tools for medicine and research. Because they are RNA molecules so they can restrict the translation of mRNA. They are very useful for treatment of mutations and chromosomal abnormalities. On the basis of their functions, the following options are true. (Option 1) – To counteract viral infections. Viruses infect by expressing their RNA or expression after transcription of DNA. So, blocking the mRNA of virus is crucial to restrict their infections. (Option 2) - To block expression of an abnormal gene responsible for disease. (Option 4) – To analyze gene function by observing what occur when the gene’s expression is inhibited. *They cannot create mutations because they are not complementary to DNA. Solution Non-coded RNA are small RNA molecule that cannot be translated by host machinery. They are useful tools for medicine and research. Because they are RNA molecules so they can restrict the translation of mRNA. They are very useful for treatment of mutations and chromosomal abnormalities. On the basis of their functions, the following options are true. (Option 1) – To counteract viral infections. Viruses infect by expressing their RNA or expression after transcription of DNA. So, blocking the mRNA of virus is crucial to restrict their infections. (Option 2) - To block expression of an abnormal gene responsible for disease. (Option 4) – To analyze gene function by observing what occur when the gene’s expression is inhibited. *They cannot create mutations because they are not complementary to DNA..