alleryMapping students to roll numbers is one-one because:
ANo two share a number
BAll students share one
CNumbers repeat freely
DEvery number is unused
Answer & Solution
Correct answer: A. No two share a number
1. Each student in the class carries a roll number of their own.
2. No two distinct students are given the same number.
3. So the mapping is one-one.
_Source: syllabus Mathematics Part I, Chapter 1, Relations and Functions._
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