To position the mother for an examination to determine if the baby is crowning, she should be placed ________.

Positioning the mother in a supine position with her knees bent and legs spread is optimal for an examination to assess if the baby is crowning. This position allows for the easiest access to view the vaginal area, as it provides a clear line of sight and facilitates the examination process for the healthcare provider. The bent knees and spread legs create an open pelvic area, which can help in assessing the progress of labor and any potential complications effectively.

In the other positions, such as lying on her side or sitting upright, visibility and access would be more restricted, making it challenging for the responder to determine the status of crowning. The standing position could also hinder a thorough examination, as it would not provide the necessary relaxation and access required to effectively monitor the situation. Hence, the supine position with knees bent and legs spread is the most appropriate for evaluating crowning during labor.