Regarding the heart valves:

• A. the aortic valve usually has two semilunar cusps
• B. the pulmonary valve is at the level of the 3rd costal cartilage
• C. they do not contain elastic fibres
• D. the tricuspid valve has anterior, posterior and medial cusps
• E. the mitral valve cusps are bigger and thinner than those of the tricuspid valve