The correct option is A at the opening of the right ventricle into the pulmonary artery
Pulmonary semilunar valve is found at the opening of the right ventricle into the pulmonary artery.
At the opening of the left ventricle into the aorta, aortic semilunar valve is found.
At the opening of the inferior vena cava into the right atrium, Eustachian valve is found.
At the opening of the coronary sinus into the right atrium, Thebesian valve is found.