Asmall population of a specific bird species lives on an island in the pacific ocean. all of the birds of this species have a crest of feathers on their heads. the color of the crest can be orange, yellow, or white. an individual's crest color does not effect its chance of survival or its reproductive success. a hurricane hits the island and all of the birds with orange crests are killed, as well as many of the individuals with yellow and white crests. this causes the gene for orange crests to be lost from the population. the loss of the gene coding for an orange crest in the bird population described above is an example of

Genetic drift

Explanation:

Genetic drift  is an evolutionary mechanism that changes the allele frequency by random sampling (by chance). This type of mechanism has the major impact when population is hit by a natural disaster. As a consequence, the population becomes reduced in size and some alleles might be lost (such as that for  for orange crests). The genetic variability is decreased.

chert is a sedimentary rock composed of microcrystalline or cryptocrystalline silica. with this little bit of information, you can come to the conclusion that your answer is c.  

explanation:

hypoxemia refers to a below usual concentration of oxygen in the blood, mainly in the arteries. hypoxemia is an indication of an issue associated with circulation or breathing and may lead to various symptoms like shortness of breath.  

the condition is identified by determining the level of oxygen in the blood sample obtained from an artery. it can also be predicted by determining the oxygen saturation of the blood with the application of a pulse oximeter.  

the normal arterial oxygen is about 75 to 100 mm hg. the values underneath 60 mm hg is generally considered with the requirement for supplemental oxygen. the normal pulse oximeter readings generally range between 95 to 100 percent. the values under 90 percent are regarded as low.  

in the given case, the oxygen saturation is measured at 93 percent, hence, there is no need to administer oxygen, that is, one should withhold oxygen.