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Question 1: Write a program named "Countvowels" that counts all occurrences of the vowels in a source string and then prints the result in the format (vowel, count). For example if the string is 'afadefsoieaid' it should print (a,3) (e,2) (i,2) (o,1) (u,0) on the screen. The program should take address of the source string as a parameter via stack. Also provide proper comments against each instruction.
Note: String is assumed to contain only small case legal letters and length of the string is fixed to 15 characters. Vowel characters include a, e, i, o, u.