The answer is C I believe
The central nervous system is made up of the brain and spinal cord<span>.</span>
refer to the taxonomic groups that are consistently utilized in organism hierarchy classification. Sub-phyla, subclasses, suborders, subfamilies, subgenera, and variations are a few examples of .
:It is challenging to classify newly discovered creatures into established categories. As a result, the prefixes "super" and "sub" have been added to the existing categories, such as sub-kingdom, sub-phylum, super class, etc. These are categorized as . This has also made the placement of different taxa more soundly and scientifically.
To learn more about refer : brainly.com/question/14196874?msp_srt_exp=4
#
Answer: D) Pulmonary and aortic valves.
Explanation
There are two main heartbeats from a healthy heart.
The first beat is called the S1 or the lub, and it occurs when the atrioventricular valves (comprising the mitral and tricuspid valves) close.
The second beat is called the S2 or the dub, and it occurs when the semilunar valves (comprising the aortic and pulmonary valves) close.
Listening for heart beats is an essential part of cardiac auscultation.