Wrong.
Using the “Manage Campaign Members” button on the “Campaign Members” related list of a Campaign record, you can add new record and/or update existing records, and you can import up to 50,000 records at a time.
You can add Leads, Contacts or person Accounts to Campaigns, but you can’t associate Opportunities to Campaigns.
Link to Salesforce Help : Manage Campaign Members
Right.
Using the “Manage Campaign Members” button on the “Campaign Members” related list of a Campaign record, you can add new record and/or update existing records, and you can import up to 50,000 records at a time.
You can add Leads, Contacts or person Accounts to Campaigns, but you can’t associate Opportunities to Campaigns.
Link to Salesforce Help : Manage Campaign Members