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: Pyruvate carboxylase is allosterically activated by one of the following compounds, what is it? 
 Options:  <1> Pyruvate. <2> Acetyl-CoA. <3> Malate. <4> Oxalacetate. <5> NAD +.

A: 2
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Q: Question: The alkali halides, MX: 
 Options:  <1> They are solids that melt below 100ºC. <2> They form crystals of intense colors. <3> They can be obtained by reaction of the M2CO3 carbonates with the aqueous solutions of the HX hydrogen halides. <4> None of them can be found in nature. <5> They are liquid at room temperature.

A: 3
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Q: Question: If a 3% false-positive test is observed in a diagnostic test, it can be stated that: 
 Options:  <1> The sensitivity is 97%. <2> The specificity is 97%. <3> The positive predictive value is 97%. <4> The specificity is 3%. <5> The sensitivity is 3%.

A:
2
****