Which of the following code segments will prevent users from being able to zoom in or out on your content?

The code segment that effectively prevents users from being able to zoom in or out on your content is the one that includes both the maximum-scale=1 and the initial-scale=1 values within the viewport meta tag. By specifying these values, you are setting the initial zoom level to 1 (100% scale) and limiting the maximum zoom level also to 1. This instructs the browser not to allow any zooming, meaning the content will always be displayed at its default size without letting users pinch to zoom in or out.

This is particularly important in responsive design, where maintaining the intended layout and usability on all screen sizes and resolutions is crucial. Users with visual impairments may need to zoom for better readability, so it's generally advisable to consider the implications of disabling zoom before implementing this in a live project.

The other choices do not effectively lock the zoom feature. One option lacks the maximum scale limitation, another claims it’s impossible to lock zoom, and the last one sets an initial scale but would allow users to zoom beyond that level, therefore it does not prevent zooming.