From what I can tell, The answer is either A or B. Mammals have what is called an Endoskeleton, which means that their skeletons are inside their bodies. A way to remember this is Exo- is similar to exit and when you exit something then you are going outside. Endo- sounds like into, which can relate to being on the inside. Insects have Exoskeletons, which are made from Chitin. Now Agonists are also called Prime Mover muscles, which means they are practically the same thing.
Patent ductus arteriosus occurs when the normal fetal circulation conduit between the pulmonary artery and the aorta fails to close and results in increased pulmonary blood flow. The clinical manifestations of patent ductus arteriosus include; Murmur; wide and bounding pulse pressure, Asymptomatic Heart failure.
Answer: The trait is recessive because individual 17 has the trait but his parents do not
Explanation: if the trait was dominant one of his parents would have to have had it.