At Ursa Major Solar, there is a single Lightning record page for the Celestial Bodies...

The correct answer is D. Component visibility filter.

In Lightning App Builder, component visibility rules can control whether a component appears based on context, including the device/form factor. Salesforce Trailhead specifically describes creating a visibility rule so a component appears only when the page is viewed on a phone, which matches restricting a Lightning component to mobile users.

A is incorrect because form factor settings are generally used for page/device availability or preview behavior, not the best feature for hiding or showing one specific component on a single Lightning record page.

B and C are incorrect because the Highlights Panel and Related List Quick Links are page components, not conditional visibility tools.

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