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'.

[EX Q]: Question: In general, allosteric enzymes: 
 Options:  <1> They link the effectors in the active center. <2> They form covalent bonds with their negative effectors. <3> They originate hyperbolic curves of speed before the concentration of substrate. <4> They change their conformation when they link effectors. <5> They are irreversibly modified when they are inhibited.
[EX A]: 4

[EX Q]: Question: A 24-year-old boy who, after 3 days of high-risk sexual contact, has numerous pustular, small, very pruritic lesions that progress to minute erosions affecting the entire glans and inner face of the prepuce. Indicate which is, among the following, the most probable diagnostic orientation: 
 Options:  <1> Genital candidiasis <2> Chancroid. <3> Secondary syphilis <4> Balanitis by Trichomonas. <5> Fungal infection by dermatophytes.
[EX A]: 1

[EX Q]: Question: The enzyme succinate dehydrogenase catalyses the dehydrogenation reaction dependent on: 
 Options:  <1> NADPH. <2> FMN <3> NAD +. <4> FAD. <5> CoA.
[EX A]:
4