Answer:
a. to treat a disease characterized by a gene that is not expressed.
Explanation:
The RNA interference (RNAi) technique is widely used in molecular biology to inhibit target gene expression at the post-transcriptional level. The RNAi technology uses small interfering RNAs (siRNAs) consisting of 18-22 nucleotides that bind to complementary acid nucleics (i.e., DNA and RNA), thereby inhibiting target gene expression. Recently, it has interestingly been discovered that small RNA sequences targeting promoter regions can also be used to activate the expression of endogenous target genes through a mechanism called RNA activation (RNAa).
For a dominant allele to be present in the phenotype, it must be present on at least one of the homologous chromosomes in the genotype.
The gene for tallness was dominant as its gene dominated the genes for for short plants