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
Which of the following cardiovascular change is abnormal in pregnancy:a) Enlarged cardiac silhouetteb) Increased S1 splitc) Right axis deviation on ECGd) Early diastolic murmure) HR increased by 10 to 15 per minute 
Select and explain. 
A. ab, B. bc, C. cd, D. ac
C: cd
Answer: C: cd 
Explanation: None