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'.

Q: Question: Gallium is the element that is under the aluminum in group 13 of the periodic table. Thus: 
 Options:  <1> It burns in oxygen giving Ga2O. <2> It is stable to air due to a protective oxide layer. <3> It dissolves very quickly in nitric acid. <4> It is not soluble in basic water with hydrogen evolution. <5> It has a melting point a little higher than aluminum.

A: 2
****
Q: Question: Indicate which of the following statements is true about bilirubin: 
 Options:  <1> It is a catabolic product of the heme group. <2> It is a product of the urea cycle. <3> It is an intermediary of the Krebs cycle. <4> It is a precursor of hepatic gluconeogenesis. <5> It is a product of cholesterol degradation.

A: 1
****
Q: Question: Which of the following heterocycles is considered a bioisosterer of the catecholic system ?: 
 Options:  <1> Pyridine <2> Indole. <3> Tetrazol <4> Thiophene <5> Benzimidazole

A:
5
****