'RNA interference (RNAi)' technology has gained popularity in the last few years. Why? 1. It is used in developing gene silencing therapies. 2. It can be used in developing therapies for the treatment of cancer. 3. It can be used to develop hormone replacement therapies. 4. It can be used to produce crop plants that are resistant to viral pathogens. Select the correct answer using the code given below.

1. RNA interference (RNAi) is a natural cellular process that silences specific genes by degrading their messenger RNA (mRNA) molecules. 2. Statement 1 is correct: Because RNAi targets specific mRNA, it is a powerful tool for developing gene silencing therapies aimed at reducing the expression of disease-causing genes. 3. Statement 2 is correct: Cancer development often involves the overexpression or mutation of certain genes (oncogenes). RNAi can potentially be used to silence these specific genes, making it a potential approach for developing therapies for cancer treatment. 4. Statement 3 is incorrect: Hormone replacement therapies involve supplementing or replacing hormones that the body is deficient in. This does not typically involve gene silencing, which is the mechanism of RNAi. 5. Statement 4 is correct: RNAi technology can be used to engineer crop plants to be resistant to specific viral pathogens. The plant can be made to produce RNA molecules that trigger RNAi against the virus's genes upon infection. 6. Thus, applications 1, 2, and 4 contribute to the popularity of RNAi technology.