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: The process of bacterial sporulation occurs: 
 Options:  <1> Both Gram positive and Gram negative bacteria. <2> After the depletion of certain essential nutrients. <3> When unfavorable environmental factors such as UV light or heat appear. <4> During the exponential growth. <5> By budding of a stem cell.
[EX A]: 2

[EX Q]: Question: What kind of validity does the degree of confidence refer to, with which it can be inferred that the cause-effect relationships between the variables of an investigation are interpretable in the sense suggested by the researcher? 
 Options:  <1> Internal validity <2> External validity <3> Discriminant validity <4> Ecological validity <5> Construct validity
[EX A]: 1

[EX Q]: Question: Which of these vitamins are isoprenoid compounds? 
 Options:  <1> Vitamins A, B2, C and D. <2> Vitamins A, B2 and Folic acid. <3> Vitamins A, K and biotin. <4> Vitamins D, E and C. <5> Vitamins A, D, E and K.
[EX A]:
5