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.

osteogenesis imperfecta (oi) refers to a congenital ailment of bones. in the condition, the bones become brittle or fragile. this ailment is a general result of the defect or mutations in the genes (colia1 or colia2). this mutation results in imperfect collagen formation either in quantity or quality wise.  

there are eight kinds of oi defects, and each kind varies with certain distinctions in symptoms. the usual symptoms include frequent bone fractures, loss of hearing in infants, protruding eyes, discoloration of the white in the eyes, respiratory issues, loosening of the joints, short stature, and other symptoms.