Which two diagnostic tests are used to determine if congenital abnormalities of the nervous system are present in the fetus in utero? ct scan and mri thoracentesis and cxr ultrasound and amniocentesis ct scan and amniocentesis thoracentesis and mri?

The answer to this question would be: ultrasound and amniocentesis

A cell that dividing frequently like fetus is at more risk when exposed to radiation from CT scan or CXR.
Ultrasound is a noninvasive procedure that will not expose the fetus to radiation. It can visualize the fetus and even measure them. With amniocentesis, we can get a sample of the fetus cell. Examining the gene of the fetus could exclude genetic disorder.