What is the best title for this passage

A．waste some time wandering in the wake of the terrible bombings
B．regret later over something they should have done earlier
C．take precautions against any potential dangers at the expense of their time
D．wear plainclothes to protect passengers or repeat their request over and again

A．This article most probably appears ______.
B．in Metro brochure
C．in a newspaper
D．in a transportation journal
E．in a police warning notice