- Hybridomas is a kind of hybrid cell which is produced by fusion of antibody producing lymphocyte with tumor cell and it is used to culture monoclonal antibody.
- PCR stands for Polymerase Chain Reaction which is used for early identification of Phenylketonuria, Sickle cell anaemia.
- Bacillus anthracis is one of bioweapons which causes Anthrax disease.
- First transgenic animal for food production is Salmon while Tracy is transgenic sheep.
So, correct option is option D. 

RNAi stands for RNA interference. It is a series of processes in which short RNA sequences are used to recognize and manipulate complementary nucleic acids. These short RNA sequences consist of 20-30 nucleotides. It protects against viruses and transposable elements.