A pregnant client with a history of alcohol addiction is scheduled for a nonstress test. The nonstress test: A. Determines the lung maturity of the fetus B. Measures the activity of the fetus C. Shows the effect of contractions on fetal heart rate D. Measures the neurological well-being of the fetus

A nonstress test is a prenatal test used to monitor the health of a fetus by assessing its heart rate and response to movement. This test is typically performed during the third trimester of pregnancy and is considered to be noninvasive and harmless to both the mother and the fetus.

Now that we understand the purpose of a nonstress test, let's analyze each option: A. Determines the lung maturity of the fetus - This is incorrect. A nonstress test does not measure lung maturity; it primarily focuses on the heart rate and response to movement. B. Measures the activity of the fetus - This is correct. A nonstress test measures the heart rate of a fetus in response to its movement, which can indicate overall well-being. C. Shows the effect of contractions on fetal heart rate - This is incorrect. A nonstress test does not involve contractions or monitoring how contractions affect fetal heart rate. That would be a stress test or contraction stress test. D. Measures the neurological well-being of the fetus - This is partially correct. While the nonstress test does provide some information on a fetus's neurological well-being, it is not a comprehensive test for neurological development or function.

Based on the analysis performed in Step 2, the correct answer is: B. Measures the activity of the fetus