If I am correct, you are asking someone to find the smallest fraction.
The answer is C) 1/9
Here's why:
You want to divide the first or top number by the second or bottom number.
The option A) 6/7 is equal to 0.85714285714
The option B) 2/3 is equal to 0.6666666666
The option D) 1/2 is equal to 0.5000000000
The option C) 1/9 is equal to 0.111111111111111111
You want to find there SMALLEST decimal. Which is 1/9 or 0.1111111