The nurse teaches a pregnant woman about the presumptive, probable, and positive signs of pregnancy.
The woman demonstrates understanding of the nurse's instructions if she states that a positive sign of pregnancy is:.

Choice A rationale:

Nasal congestion and occasional epistaxis (nosebleeds) are common symptoms during pregnancy due to elevated levels of estrogen. Increased estrogen causes mucosal blood vessels to become engorged and more fragile, leading to nasal congestion and occasional nosebleeds. This is a normal respiratory change in pregnancy and not necessarily a cause for concern.

Choice B rationale:

While cardiovascular changes are common in pregnancy, nosebleeds alone are not indicative of abnormal cardiovascular changes unless they are accompanied by other symptoms. The given scenario does not provide enough information to support this choice.

Choice C rationale:

There is no evidence provided to suggest domestic violence (Choice C) as the cause of the woman's symptoms. Additionally, this choice lacks a physiological basis for the symptoms described.

Choice D rationale:

Intranasal cocaine use (Choice D) can indeed cause nasal congestion and frequent nosebleeds. However, the scenario does not provide any information to support this choice, and assuming drug use without evidence is not appropriate.

Choice A rationale:
Pulmonary stenosis is characterized by a systolic ejection murmur best heard at the upper left sternal border. It does not typically produce a continuous machinery-like murmur. Pulmonary stenosis results from narrowing at the pulmonary valve, obstructing blood flow from the right ventricle to the pulmonary artery.
Choice B rationale:
A continuous machinery-like murmur is characteristic of patent ductus arteriosus (PDA). PDA is a congenital heart defect where the ductus arteriosus, a fetal blood vessel that should close after birth, remains open, allowing continuous blood flow between the aorta and pulmonary artery. This murmur is often best heard in the left infraclavicular region.
Choice C rationale:
Ventricular septal defect (VSD) typically produces a harsh holosystolic murmur heard best at the lower left sternal border. VSD is a hole in the septum separating the ventricles, allowing blood to flow from the higher-pressure left ventricle to the lower-pressure right ventricle.
Choice D rationale:
Coarctation of the aorta causes a murmur due to increased blood flow across the aortic valve. However, this murmur is not continuous and is usually systolic and best heard in the back over the left scapula.