Change Sets are a point-and-click tool for migrating metadata between related Salesforce orgs, such as from a sandbox to a production org.
Option C: Deployment is done in a one-way, single transaction.
Correct.
Change sets are deployed in a one-way direction from the source org to the destination org.
The deployment occurs in a single transaction. If any component fails to deploy, the entire deployment is rolled back.
Before deploying a change set, you must set up a deployment connection between the source and destination orgs.
This connection is established through the Setup menu under Deployment Connections.
Change sets can only be sent between orgs that are affiliated, such as a sandbox and its production org, or sandboxes that are clones of the same production org.
They cannot be used between unrelated orgs.
Change sets can deploy the metadata of custom settings (the definition), but not the actual data stored within them.
To move custom settings data, you must use a data migration tool like Data Loader.
Change sets are designed to transfer metadata components, not data records.
To transfer data records, use tools like Data Loader or Data Import Wizard.
Reference:
Deploy Change Sets
Option D: Sending a change set between two orgs requires a deployment connection.
Correct.
Create Deployment Connections
Option E: Change sets can only be used between related organizations.
Correct.
Change Sets Overview
Incorrect Options:
Option A: Change sets can deploy custom settings data.
Incorrect.
Change Set Considerations
Option B: Change sets can be used to transfer records.
Incorrect.
Deploy Metadata with Change Sets
Conclusion:
The three characteristics of change set deployments are C, D, and E.