Choose the correct option:
People taking drugs are at increased risk of having AIDS because of ________.

Q. People taking drugs are at increased risk of having AIDS because of sharing syringes.

Q. People taking drugs are at increased risk of having AIDS because of :

Q. People taking drugs are more prone to AIDS because of .

Q. Assume that the chances of a patient having a heart attack are $40\%$. It is also assumed that a meditation and yoga course reduce the risk of heart attack by $30\%$ and the prescription of certain drugs reduces its chances by $25\%$. At a time a patient can choose any one of the two options the patient selected at random suffers a heart attack. Find the probability that the patient followed a course of meditation and yoga?