What do you need to use to adjust levels in an image?

To adjust levels in an image, the appropriate method is to use the "Levels" adjustment found under the Image menu. This brings up the Levels dialog box, which allows the user to modify the tonal range of the image by adjusting the shadows, midtones, and highlights. This tool is essential for correcting exposure problems and enhancing the overall contrast of an image.

While creating a new adjustment layer for levels is also a valid method to achieve similar results, it falls under a different category as it applies non-destructive editing, which is not explicitly mentioned in this context. The Brightness/Contrast option adjusts overall brightness and contrast but does not provide the granular control over tonal ranges that the Levels tool does. The Filters option for adjusting levels does not exist in Photoshop, making it not applicable in this scenario.