After having robbed the bank, ___________.

The completion of the sentence "After having robbed the bank, ___________" is best suited by the phrase "The thief hid at the house of a friend" because it logically follows the given context of the sentence. This completion indicates a direct consequence of the action mentioned – the robbery. After committing such an act, it is plausible that the thief would seek refuge to avoid capture, making this choice the most fitting in terms of cause and effect.

Additionally, this option paints a clear picture of the immediate circumstances following the bank robbery, indicating the thief's need for concealment. The other choices present events that, while they may be related to the robbery, do not depict a direct result of the action in the same immediate context. These statements could occur but do not reflect the immediate aftermath directly associated with the act of robbery as clearly as the chosen option does.