Final answer:
The priority assessment for a suspected cerebrovascular accident is the respiratory rate, as it reflects the most immediate life-threatening condition and requires prompt address.
Step-by-step explanation:
When assessing a client who has had a suspected cerebrovascular accident (CVA) or stroke, a nurse should place priority on the finding that reflects the most immediate life-threatening condition. Among the options provided - blood pressure, pupil size and reaction to light, respiratory rate, and grip strength - the primary focus should be on the respiratory rate. This is because airway and breathing are critical and can be compromised following a stroke, posing a significant risk to the patient's life. An abnormal respiratory rate may indicate brain stem involvement or decreased consciousness, which requires immediate intervention.