To determine the domain of the square root function graphed, we observe where the graph exists along the x-axis, since the domain refers to the set of all possible x-values for which the function is defined.

From the graph:

• The function starts at $x = 1$ and extends to the right.
• There are no parts of the function graphed for $x < 1$.

Therefore, the domain of this square root function is: $x \geq 1$

The correct answer is: $x \geq 1$.

Would you like more details or have any questions?

Here are some related questions:

1. What is the range of this square root function?
2. How do you determine the domain of a square root function in general?
3. What transformations could shift this square root graph horizontally?
4. How does the domain change if we reflect the graph across the y-axis?
5. What happens to the domain if we consider a square root function with a vertical stretch?

Tip: When determining the domain of a square root function, remember that the expression inside the square root must be non-negative (greater than or equal to zero).