Chapter 13 - A Preview of Calculus: The Limit, Derivative, and Integral of a Function - Section 13.3 One-sided Limits; Continuous Functions - 13.3 Assess Your Understanding - Page 909: 5

True

When the denominator value of a rational functions is 0, then the function has a "hole" and is undefined. For example: $f(x)=\dfrac{1}{x}$ has a hole at $x=0$ (when the denominator value is 0). Therefore, the given statement is $\bf{True}$.