<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 45-year-old primigravida woman at 13-weeks gestation is scheduled for a prenatal evaluation. This is her first appointment, though she has known she is pregnant for several weeks. A quad screening is performed with the mothers blood and reveals the following:AFP alpha-fetoprotein DecreasedhCG human chorionic gonadotropin ElevatedEstriol DecreasedInhibin ElevatedUltrasound evaluation of the fetus reveals increased nuchal translucency. Which mechanism of the following mechanisms is most likely to have caused the fetuss condition?? A: Robertsonian translocation, B: Nondisjunction, C: Nucleotide excision repair defect, D: Mismatch repair, E: Mosaicism,  <response>: This is a question about interpreting abnormal prenatal screening results to identify the most likely underlying genetic mechanism causing the fetuss condition. The key findings are decreased AFP, elevated hCG, decreased estriol, elevated inhibin, and increased nuchal translucency on ultrasound. The choices include different genetic mechanisms: A Robertsonian translocation - a balanced translocation between two acrocentric chromosomes. This would not cause the abnormal biomarker levels seen.B Nondisjunction - failure of chromosomes to properly separate during meiosis or mitosis. This can lead to aneuploidy which could explain the abnormal screening results. C Nucleotide excision repair defect - a DNA repair defect. This would not lead to the findings seen. D Mismatch repair - a DNA repair mechanism. Defects can lead to microsatellite instability but would not cause the screening abnormalities.E Mosaicism - presence of two cell lines with different genotypes. Could potentially explain the findings if there is mosaic aneuploidy.B: Nondisjunction 