What would be the most difficult part of using a specific sirna to reduce expression of a human gene involved in the development of cancer or whose product allows for the expression of viral-encoded proteins?
choose one or more:
a. identifying an sirna that is effective in targeting a specific mrna
b. delivering sirna to cells in the body
c. determining the effectiveness of the sirna in cells
d. reducing potentially harmful side effects of sirna activity

The correct answer is B delivering siRNA to cells in the body

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.

i would say it is