Which of the following is true regarding blood pressure measurement and cuff size?

The statement that the cuff bladder should encircle at least 80% of the upper arm is accurate and crucial for obtaining precise blood pressure readings. Proper cuff size is essential because if the cuff is too small for the person's arm, it can result in falsely elevated blood pressure readings. Conversely, a cuff that is too large may give falsely low readings. The recommendation for the cuff to encircle a minimum of 80% of the upper arm ensures that the pressure applied is evenly distributed and that the arterial wall is compressed adequately, allowing for accurate assessment of blood pressure levels.

In terms of the other choices, measuring in a quiet environment does not eliminate the importance of selecting the right cuff size. There are established guidelines for cuff sizing regardless of the measurement environment. A larger cuff may help mitigate inaccuracies, but it does not necessarily "compensate" — the readings could still be misleading if the cuff doesn’t fit appropriately for the individual's arm size. Lastly, measuring blood pressure on the forearm with a standard cuff is not accepted practice and does not provide reliable results; blood pressure readings should be taken using the upper arm for standard measurements.