Final answer:
The use of sound for eliciting fetal movement and accelerating FHR is called a nonstress test, used in prenatal care to ensure fetal health. So, the correct answer is B.
Step-by-step explanation:
The use of sound to elicit fetal movement and accelerate Fetal Heart Rate (FHR) is known as a nonstress test (Option b). This test involves playing sounds to the fetus and monitoring the response in the form of fetal movements and changes in the heart rate. The nonstress test is an integral part of prenatal care and helps in assessing the fetal well-being without causing stress to the fetus. Ultrasounds utilize high-frequency sound waves beyond human hearing capabilities and are commonly used to observe the fetus during pregnancy. The primary goal of a nonstress test is to ensure that the fetus is healthy and that the pregnancy is progressing normally.