Step 1: Recall the cardiac conditions in which pregnancy is contraindicated because of unacceptably high maternal mortality (mWHO class IV).
Step 2: Severe pulmonary arterial hypertension carries very high maternal mortality because the fixed high resistance cannot accommodate the increased cardiac output and volume of pregnancy, so pregnancy is contraindicated. Eisenmenger syndrome (a reversed shunt with pulmonary hypertension) is one of the most dangerous, with maternal mortality of 30 to 50 percent, and is contraindicated. Marfan syndrome with a dilated aortic root (commonly > 4 to 4.5 cm) carries a high risk of aortic dissection and rupture in pregnancy, so it too is contraindicated.
Step 3: Consider WPW syndrome. It is a pre-excitation arrhythmia syndrome. It may cause supraventricular tachycardia, but it does not impose the prohibitive maternal mortality of the other three and can be managed; it is not a contraindication to pregnancy.
Step 4: Hence WPW syndrome is the option that is NOT a contraindication.
Answer: Option A, WPW syndrome.