Read the following directions on a bottle of medicine:     "Take two tablets with water, followed by one tablet every eight hours, as required, For maximum night-time and early morning relief, take two tablets at bed - time, Do not take more than six tablets in twenty-four hours.      For children six to twelve years old, give half the amount for a grownup. For children under six years old, ask for your doctor's advice.     Reduce the amount if nervousness,  _ , or sleeplessness occurs," Obviously the medicine   _   .
may be dangerous to small children. cannot be taken by children under twelve years old. may be taken by children but not by grown-ups. may be taken by grown-ups but not by children.