Final answer:
The correct pulse rate for a two-year-old patient that an EKG technician should recognize as within the expected reference range is option (b) 100 beats per minute, which is within the normal range for toddlers.
Step-by-step explanation:
An EKG technician checking the pulse rate for a two-year-old patient should identify a rate within the expected pediatric range. For a two-year-old, a normal pulse rate can range from about 80 to 130 beats per minute. Hence, the correct answer to the student's question is option (b) 100 beats per minute, which falls within the expected reference range for a toddler's heart rate.
Infants typically have a higher pulse rate which is measured to be around 130 ± 5 beats per minute. The pulse rate naturally decreases as a child grows older, settling into a lower average rate in adulthood. It's important to note, trained athletes can have resting heart rates much lower than the general population without indicating a medical condition such as bradycardia. However, pulse rates lower than expected ranges for specific age groups, such as below 60 beats per min in adults or below 80 beats per minute in toddlers, may require medical attention.