Answer:
First choice
Step-by-step explanation:
The domain refers to all possible values that could be plugged into the function.
The first choice, [tex]\frac{1}{1-x}[/tex], will not be valid for the value [tex]x=1[/tex] because when [tex]x[/tex] is 1 the denominator becomes zero.
Division by zero will produce an undefined result, which would be represented by an asymptote when graphing the function.
