The correct option is B.
Having short breath and sharp pains in the chest are indications of cardiac distress and it indicate that the heart is been exerted upon. The first thing the nurse should do is to ask the patient to sit down in order to reduce the exertion force on the heart. Resting will allow the patient to become stabilized, the nurse can then check the patient's need for oxygen application.
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Duplications are repeated segments of genetic materials that result from unequal crossing over during meiosis or through a replication error prior to meiosis. They usually occur when homologous pairs do not line up correctly or in chromosomes with a lot of repeat sequences. Duplication of a segment of a chromosome would result in Genetic variability during evolution due to gene duplication.
The geosphere is the solid part of the earth. It has three components which are: the core, mantle and the crust. Thus, the mantle is a component of the geosphere.