Marked changes occur in the cardiopulmonary system at birth include which of the following? Note: ...

1, 2, 4
Explanation: 1. Closure of the foramen ovale is a function of changing arterial pressures.
2. Closure of the ductus venosus is related to mechanical pressure changes that result from severing the cord, redistribution of blood, and cardiac output.
4. Increased systemic vascular resistance and decreased pulmonary vascular resistance; with the loss of the low-resistance placenta, systemic vascular resistance increases, resulting in greater systemic pressure. The combination of vasodilation and increased pulmonary blood flow decreases pulmonary vascular resistance.

I know you spent a lot of time finding this because I swear it wasn't in my textbook