Multi-client accounts (MCAs) in Google Merchant Center allow advertisers to easily:

Multi-client accounts (MCAs) in Google Merchant Center allow advertisers to easily:

  • A) Combine reporting on all data feeds across domains
  • B) Share products between accounts
  • C) Manage multiple domains with a single sign in
  • D) Access multiple AdWords accounts

The correct answer is:

  • C) Manage multiple domains with a single sign in

Explanation: Merchant Center multi-client accounts allow a single person or company to submit data feeds for multiple domains. Each client may have a distinct store name and URL. When you request a multi-client account, your current Google Merchant Center account will become a sub-account in your new multi-client account.

Read more here: https://support.google.com/merchants/answer/188487?hl=en