Having a cellphone also makes us feel safer, since we can call for help in case of an  e__________ (紧急情况).

Having a cellphone also makes us feel safer, since we can call for help ________ an emergency.

1. A.
   as a result of
2. B.
   according to
3. C.
   in case of
4. D.
   because of

Having a cellphone also makes us feel safer, since we can call for help ________ an emergency.

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