Final answer:
The correct answer is b) Layer > Flatten Artwork, which merges all layers and objects onto a single layer in Adobe Illustrator and preserves their visual stacking order.
Step-by-step explanation:
To organize all objects onto a single layer with no sublayer while preserving the stacking order and renaming the layer to 'final', the correct option would be b) Layer > Flatten Artwork. This function is typically used in Adobe Illustrator and what it does is it merges all layers, sublayers, and objects within the document onto a single layer, therefore eliminating any sublayers and grouping but preserving the visual appearance of the artwork. Once flattened, simply double-click on the layer to rename it to 'final'. Options a) Layer > Merge Layers and d) Layer > Merge Selected could potentially merge only the selected layers or objects which might not include all objects or could disrupt the stacking order. Option c) Layer > Collect in New Layer would move the selected objects to a new layer but would not remove sublayers or merge objects.