What number should be called for life-threatening injuries?

For life-threatening injuries, the number to call is 911. This is the emergency hotline utilized in the United States for urgent situations requiring immediate assistance from police, fire, or medical responders. When someone is faced with a severe injury, time is crucial, and dialing 911 ensures that emergency services can reach the incident location as quickly as possible.

The other numbers listed serve different purposes and are not appropriate in emergencies. For instance, 311 is typically a non-emergency service number that helps to report municipal issues or seek information about city services, while 411 is often used for directory assistance. The number 555 is generally reserved for fictional use in entertainment and is not an active emergency contact. Thus, calling 911 is the correct choice in life-threatening scenarios to secure prompt help.