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'.

Example Input: Question: We want to study if Vitamin D can increase the incidence of breast cancer. In our area we have a population registry of cancer. To achieve our goal, all women diagnosed with breast cancer are selected from the register we have and each case pairs with two controls. What study design has been chosen? 
 Options:  <1> Prospective cohort study. <2> Cases and controls study. <3> Case-control study nested. <4> Retrospective cohort study. <5> Ecological study
Example Output: 3

Example Input: Question: A 16-year-old woman consulted for primary amenorrhea. It presents a normal female development of secondary sexual characteristics. The levels of estradiol and testosterone are normal. In the gynecological examination, agenesis of the vagina is appreciated. Ultrasound is performed and there is absence of uterus. The ovaries are normal ultrasound. No left kidney is seen. The most likely diagnosis is: 
 Options:  <1> Rokitansky syndrome. <2> Morris syndrome. <3> Congenital adrenal hyperplasia. <4> Polycystic ovarian syndrome. <5> Kallman syndrome.
Example Output: 1

Example Input: Question: Which of the following excipients acts as a plasticizer in hard gelatine capsules? 
 Options:  <1> Jelly. <2> Titanium dioxide. <3> Glycerin. <4> Sodium bisulfite. <5> For methyl aminobenzoate.
Example Output:
3