Final answer:
The correct emergency services number to dial is c. 911, which is applicable in the United States for immediate help in dangerous situations or health emergencies.
Step-by-step explanation:
The emergency services number to dial is c. 911. When you dial 911, you're connected to a dispatcher who will direct your call to local emergency services such as the police, fire department, or ambulance. It's important to call 911 only in cases of immediate danger or when someone's health or safety is at risk. Remember that 911 is specific to the United States and other countries may have different emergency service numbers, such as 000 in Australia and 112 in many European countries.