Choose the correct preposition

1. The city had to resort
   [to|in] policemen directing traffic when the traffic computer system crashed.
2. Governments are very concerned about the threat
   [from|of] cyber terrorism.
3. The road signs displayed
   [to|on] drivers were all wrong.
4. So many essential public services rely
   [on|to] computers to operate.
5. There is a worm capable
   [of|at] stealing your computer passwords.