This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Gynaecology & Obstetrics
Fetal heart tracing findings in case of maternal carbon monoxide poisoning includes all except 
Select and explain. 
A. Elevated baseline, B. Absence of accelerations, C. Marked beat-to-beat variability, D. Decreased beat-to-beat variability
C: Marked beat-to-beat variability
Answer: C: Marked beat-to-beat variability 
Explanation: Fetal heart rate pattern in maternal carbon monoxide poisoning shows:
→ Elevated baseline
→ Diminished variability
→ Absent accelerations and decelerations.