The UX team has suggested that “Social share” buttons currently visible in the sidebar region...

In Drupal 10 and Drupal 11, blocks are placed and managed through the Block Layout system available at Structure → Block layout . Each theme defines regions such as Sidebar, Footer, Header, etc., and administrators can assign blocks to these regions.

Since the “Social share” buttons are implemented as a custom block , the correct approach is to reposition the block using the Block Layout admin interface . This interface allows site builders to move blocks between regions either by dragging or by editing the block’s region setting. This matches Drupal’s documented site-building practice for managing block placement.

Option A is incorrect because Manage display is used for configuring how fields are displayed on entities, not for block placement. Option C is incorrect because the Appearance page controls themes, not individual block placement. Option D is unnecessary because Layout Builder is used for per-content or per-entity layouts, not for globally placed blocks like a social share block.

Therefore, the simplest and correct solution is to move the block via the Block Layout page, making option B correct.