Which resolution is considered the highest among the following options?

The resolution identified as the highest among those listed is 4K. This resolution, also referred to as Ultra HD, offers a pixel count of 3840 x 2160, which is four times the resolution of 1080p. This increased pixel density provides greater detail and clarity, making 4K particularly advantageous for large displays and for producing visually stunning content.

In comparison, 720p, or HD Ready, has a resolution of 1280 x 720, which is lower than both 1080p (1920 x 1080) and 1080i, a format of 1080p that uses interlaced scanning. While 1080p and 1080i offer good quality images for standard viewing, they do not compete with the superior detail and quality provided by 4K resolution. Therefore, given its higher pixel count and enhanced visual richness, 4K stands out as the best option in this context.