Final answer:
The nurse should schedule an ultrasound to determine gestational age and verify the client's report of feeling fetal movements, which align with the common experiences of the second trimester.
Step-by-step explanation:
The best response by the nurse in this scenario would be to schedule an ultrasound to determine gestational age. Given that the client's last period was 5 months ago, and they are feeling fetal movement, it is entirely possible these experiences relate to the second trimester of pregnancy. At about 20 weeks, or roughly 5 months, it is commonly reported that the mother can feel fetus movements, corroborating the client's account. Therefore, option B is the most appropriate and professional action to take considering nursing and prenatal care practices. A pelvic exam alone cannot confirm the gestational age, and informing the client that feeling the baby move is not possible is incorrect and could be considered dismissive of the client's experiences. The initial visit is also a good time to congratulate the client, but the primary concern should be to confirm pregnancy details through an ultrasound and gather additional pregnancy-related health information.