Final answer:
During hyperventilation, breathing depth and rate increase due to input from chemoreceptors, but this leads to abnormally low blood carbon dioxide levels and an increase in blood pH.
Step-by-step explanation:
When a person hyperventilates, the correct statement is c) input from chemoreceptors will trigger an increase in breathing depth and rate. However, this input is based on the body's attempt to restore normal levels and does not apply directly to the immediate consequence of hyperventilation. In fact, hyperventilation leads to an abnormally low blood carbon dioxide levels and a higher, more alkaline, blood pH. It does not cause the partial pressure of oxygen in the blood to become higher than normal (option a), alveolar ventilation to be lower than during normal breathing (option b), or the partial pressure of carbon dioxide in the blood to become higher than normal (option d). Instead, it causes the opposite of option d - a decrease in the partial pressure of carbon dioxide.