Final answer:
The risk factor that is not associated with neural tube defects is the mother being underweight. Adequate folate consumption, obesity, family history of spina bifida, and being of Hispanic ethnicity are recognized as risk factors. Intake of folic acid prevents NTDs like spina bifida.
Step-by-step explanation:
The question is about identifying which option is not a risk factor for neural tube defects (NTDs). NTDs are serious birth defects of the brain and spine, such as spina bifida and anencephaly. Factors that increase the risk of NTDs include inadequate folate intake during pregnancy, obesity of the mother, family history of spina bifida, and certain ethnicities, such as Hispanics, which have been observed to have higher rates of NTDs. However, being underweight is not commonly cited as a risk factor for neural tube defects, while obesity is. Therefore, the correct option is (c) The mother being underweight.
It's essential for expectant mothers to ensure sufficient intake of folic acid during the early stages of pregnancy to reduce the risk of NTDs. A deficiency in folic acid can lead to an increased risk of a child being born with spina bifida or anencephaly. Preventive measures like folate supplementation, maintaining a healthy weight, and avoiding harmful substances such as certain medications, excessive alcohol, and radiation can help reduce the incidence of these birth defects.