The best Lightning component to add to the layout to display the 'New Task' custom action is Highlights panel. This component shows key information and actions for a record, such as its name, owner, and custom actions. Related record, related lists, and activities are not Lightning components that display custom actions.
See [this article] for more information on Highlights panel.

To allow users access to Flows, Salesforce offers multiple integration points:
* A. Quick Action: Flows can be initiated from record pages, the app utility bar, or global actions using Quick Actions. This allows users to execute flows relevant to specific records or global processes.
* C. Flow Launcher: A component available in Lightning App Builder that enables users to start flows directly from a Lightning page.
Steps to set up these features:
* For Quick Actions, navigate to Setup # Object Manager # select object # Buttons, Links, and Actions # New Action # Action Type (Flow).
* For Flow Launcher, navigate to Lightning App Builder # select the page # drag the Flow component to the desired section of the page # configure it to launch the specific flow.
For more information on integrating Flows, check the Salesforce documentation on Flow Distribution.

The two reasons that could be preventing this relationship conversion are that there are already two master- detail relationships on the Invoice Line Item and that Invoice Line Item records exist without having the Invoice lookup field populated. A custom object can have up to two master-detail relationships, so adding another one would exceed the limit. Also, a master-detail relationship requires that the detail records have a value in the master lookup field, so any records with a blank Invoice lookup field would prevent the conversion.

All data should be backed up before converting a text field to a picklist, as some data may be lost or truncated during the conversion. Changing a field type will remove existing field history, as the history tracking values are not converted

To ensure sales reps input contacts into Salesforce rather than their personal devices:
* C. Enable offline create, edit, and delete in Salesforce for Android and iOS. This feature allows sales reps to enter contact information directly into the Salesforce Mobile App even when they are offline, which syncs back to Salesforce once connectivity is restored.
Steps to enable offline capabilities:
* Navigate to Setup # Mobile Administration # Salesforce Mobile App # Offline Settings.
* Configure offline settings to allow for creating, editing, and deleting records.
* Ensure that the Contact object is available for offline access.
This functionality encourages reps to use Salesforce directly by mitigating connectivity constraints.
For implementation details, refer to Salesforce Mobile App Offline.