Ans. is 'a' i.e., 1% Common modes of transmission of HIV and their relative riskTypes of exposureApproximate chance of infection per exposureI Sexual intercourse: anal, vaginal, oral01-10%II Blood and blood products. Factor VII etc. Blood transfusion> 90%III Tissue and organ donation, semen, cornea, bone marrow, kidney etc.50-90%IV Injections and injuries shared needles by drug addicts Injections with unsterile Needle-stick and other injuries in health staff? Surgical wounds0-5-10%V Mother to baby :TransplacentalAt birthAfter birthBreast milk30%