Bacteria that live around deep-sea, hot-water vents obtain energy by oxidizing inorganic hydrogen sulfide belched out by the vents. they use this energy to build organic molecules from carbon obtained from the carbon dioxide in seawater. these bacteria are
a. chemoheterotrophs
b. photoheterotrophs
c. chemoautotrophs
d. photoautotrophs

Chemoautotrophs.

Explanation:

Autotrophs may be defined as the organism that can prepare their own food with the help of chemical and light. Two types of autotrophs are chemoautotroph and photoautotrophs.

Chemoautotrophs are the organisms that can prepare their own food with the help of chemicals. The bacteria living around deep sea and hot water vents are considered as chemoautotrophs because they prepare their food with the help of carbon present in their surroundings.

Thus, the correct answer is option (A).

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.