Answer:
The correct answer is B delivering siRNA to cells in the body
Step-by-step explanation:
siRNA or small interfering ribonucleic acid plays an important role in gene silencing.
siRNA exerts its gene silencing effect by binding with its specific mRNA at translation level thus blocking the translation of that mRNA.
But the principle difficulty of using a specific siRNA to reduce expression of a cancer causing genes is delivering the desired siRNA to specific cells in the body because if by mistake the desired siRNA is being targeted to the normal body cell instead of cancer cell then it(siRNA) will block the functioning of that normal body cell resulting in the development another problem rather than solving one problem.