A CA may take a patient’s height and weight under which conditions?

A chiropractic assistant (CA) may take a patient's height and weight without direct supervision because this task is considered a routine and straightforward measurement that does not require the chiropractor to be present at all times. Such measurements are typically non-invasive and do not involve any diagnostic or clinical judgment, making them suitable activities for a trained assistant to perform independently. This allows for the efficient flow of patient care while ensuring that CAs contribute to gathering essential patient information.

The other options imply a need for supervision or additional conditions that are not necessary for taking simple measurements like height and weight. This reflects a proper understanding of the roles and responsibilities of chiropractic assistants within their professional scope.