Final answer:
Severe persistent headache and visual disturbances would be considered abnormal.
Step-by-step explanation:
The physiological changes that occur during pregnancy can affect every body system. It is important to understand what symptoms or presentations are considered normal and which ones may be abnormal. In this case, out of the given options, severe persistent headache and visual disturbances would be considered abnormal.
Mild lower back pain is a common discomfort in pregnancy due to the changes in posture and the growing uterus. Swollen ankles and feet, known as edema, can occur due to the increased blood volume and pressure on blood vessels. An increase in heart rate during physical activity is a normal response as the body adapts to the increased demands of pregnancy.