You will be given a definition of a task first, then some input of the task.
In this task, you are given a multiple-choice question about healthcare. Answer the question based on your information and classify your answers into '1', '2', '3', and '4'.

Question: Which of the following statements is INCORRECT in relation to the alterations of the acid-base balance?
Options: <1> The arterial pH is regulated by the Henderson-Hasselbach equation and is 7.35-7.45. <2> Hypercapnia (increase in PaCO2) is a consequence of the increase in CO2 production. <3> Metabolic acidosis occurs due to increased endogenous acid production, acid accumulation and / or loss of bicarbonates. <4> In patients with lactic acidosis it is common to find an anion gap or difference greater than 12 mmol / L. <5> The use of alkalizing solutions should be reserved for cases of severe acidemia with ph <7.20.
Output:
2