Google Merchant Center is used for:

  • A) Setting up campaign bidding priorities
  • B) Managing conversion tracking
  • C) Editing your Shopping campaign’s product groups
  • D) Uploading product data feeds

The correct answer is:

  •  D) Uploading product data feeds

Explanation: Google Merchant Center is a tool that helps you upload your store and product data to Google and make it available to Google Shopping and other Google services.

Read more here: https://support.google.com/merchants/answer/188493