Final answer:
All the methods listed: oral, rectal, axillary (armpit), and tympanic (ear) are generally accepted ways to measure body temperature. The axillary method might be considered slightly less reliable because it is affected by external factors, but all methods are clinically acceptable.
Step-by-step explanation:
All the methods listed: oral, rectal, axillary (armpit), and tympanic (ear) are commonly accepted ways to measure a person's body temperature. Each has its own level of accuracy, with oral and rectal usually being the most accurate. The axillary method might be slightly less reliable because it is influenced by external factors like clothing and room temperature.
In reality, the choice of method often depends on the situation and the person's condition. The least invasive and simplest method, would be preferable for routine checks. Therefore, none of the methods mentioned in your question can be unanimously ruled out as 'not reliable' for taking a person's temperature.
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