A recent study on medicine addiction found out that there are principally three main factors that determine the risk of becoming dependant on or addicted to medicines. The first factor is the type of medicine, the second is the personality of the individual, and the third factor is controlled by the circumstances in which the medicine is taken. As a parallel example, we only need to look as far as alcohol. While it could be safely said that the majority of the adult population have taken alcohol, yet only a small proportion of these go on to get addicted to alcohol. Besides, it is well documented that many strong medicines that have been used for medical purposes have not caused the patient to become addicted. However, the study found that people who took medicines for the heck of it were more likely to become dependent on the same. The dependence need not be restricted to the physiological side but may become psychological, although the effects are still essentially the same. People with psychopathic, immature or otherwise unstable personalities were shown to be at the greatest risk of becoming addicted.

Question: Long-term use of certain drugs for medical purposes does not cause addiction.
Options:
A. true, B. false, C. uncertain
Answer: "B"