Charting Temperature Sites

I was taught to chart temperature as follows:

T98.2 (it's assumed be an oral temperature unless otherwise indicated, so no need to write the site down)
T98.2 A (for axillary)
T98.2 R (for rectal)
T98.2 TY (for tympanic membrane)

In preparation for taking my CNA examination, I was reading the procedure list from my state manual and it stated I must record the site used to take the temperature. It appears that they only test for oral temperatures.

What should I put for the oral site? I'm guessing it would be, for example, T98.2 O. Is that right?