The square root function's range spans all real numbers, as its inherently positive nature ensures values greater than or equal to 0. Option d is the correct choice.
The function's range encompasses all real numbers due to the inherent positivity of the square root function. Since the square root of any non-negative number is always positive, the function inherently produces values greater than or equal to 0. The graphical representation of the function further validates this conclusion, illustrating a continuous and uninterrupted curve that extends from 0 to infinity on the y-axis.
This visual confirmation aligns with the mathematical reasoning, substantiating that the function spans the entirety of real numbers, with no gaps or holes in its range. In summary, the comprehensive coverage of values, both mathematically and graphically, affirms that the range of the square root function is indeed all real numbers. So, Option d is the correct choice.