Final answer:
The true statement about respiratory acidosis is that it is characterized by a higher than normal amount of carbon dioxide in the blood, leading to a decrease in blood pH and overly acidic blood.
Step-by-step explanation:
The correct answer to the question 'Which of the following is true of respiratory acidosis?' is that c. the amount of carbon dioxide in the blood is greater than normal. Respiratory acidosis is a condition characterized by an excess of carbonic acid or CO2, which causes the blood pH to decrease below the normal level of 7.35-7.45, thereby making the blood overly acidic.
It is typically a result of conditions that impair respiration, such as emphysema, pneumonia, or congestive heart failure, which lead to hypoventilation and an accumulation of CO2 in the blood. In contrast, hyperventilation leads to respiratory alkalosis by excreting too much CO2, which would increase blood pH and make the blood overly alkaline. Therefore, travelling to high altitudes or hyperventilation are not causes of respiratory acidosis.