Which of the following resolutions is commonly known as Ultra HD?

Comprehensive and Detailed In-Depth Explanation:

Ultra HD (UHD), also referred to as 4K UHD, has a resolution of 3840x2160. It's four times the resolution of standard 1080p (Full HD), offering more screen real estate and sharper images.

Option A (1920x1080): Full HD (FHD), not UHD.

Option B (2048x1080): DCI 2K — used in cinema, not common for Ultra HD.

Option D (7680x4320): Known as 8K UHD, not standard Ultra HD.

CompTIA A+ Core 1 Exam Objective Reference:

Objective 1.7: Compare and contrast display technologies and their features.

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