An ordinal number that shows the beginning number of a set is called First.
'First' is also written as "1st".
Consider the set of vowels, V = {a, e, i, o, u}. This set starts with the letter `a`, so `a` is the First element of the set V.
A. 18
B. 5
C. 8
D. 15
Correct Answer: A
Step 1: An ordinal number that shows the beginning number of a set is called First.
Step 2: In the given set, 18 is the first number.