Option A
26 and 99 are relatively prime numbers
Solution:
Let us first understand about relative prime numbers
Two integers a and b are said to be relatively prime, mutually prime, or co prime if the only positive integer (factor) that divides both of them is 1
Let us check the options
Option A
26 and 99
The factors of 26 = 1, 2, 13, 26
The factors of 99 = 1, 3, 9, 11, 33, 99
Thus there no common factors other than 1
So 26 and 99 are relatively prime numbers
Option B
90 and 117
The factors of 90 = 1, 2, 3, 5, 6, 9, 10, 15, 18, 30, 45, 90
The factors of 117 = 1, 3, 9, 13, 39, 117
Here 3 and 9 are common factors
So 90 and 117 are not relative prime numbers
Option C
100 and 202
The factors of 100 = 1, 2, 4, 5, 10, 20, 25, 50, 100
The factors of 202 = 1, 2, 101, 202
Here 2 is a common factor
So 100 and 202 are not relative prime numbers
Option D
201 and 444
The factors of 201 = 1, 3, 67, 201
The factors of 444 = 1, 2, 3, 4, 6, 12, 37, 74, 111, 148, 222, 444
Here 3 is common factor
So 201 and 444 are not relative prime numbers