Prospects sync to your CRM when they have been assigned to a user or queue. A CRM is a customer relationship management platform that allows you to manage your sales and customer service operations. You can integrate Marketing Cloud Account Engagement with your CRM using the Salesforce connector, which allows you to sync data, activities, and campaigns between Marketing Cloud Account Engagement and Salesforce. However, not all prospects in Marketing Cloud Account Engagement are synced to Salesforce. Only prospects that have been assigned to a user or queue in Marketing Cloud Account Engagement are synced to Salesforce as leads or contacts. You can assign prospects manually, through automation rules, or through lead assignment rules.

Answer A, C, D, and E are incorrect because prospects do not sync to your CRM when they fill out a form on a landing page, when they have a lead score greater than 50, when they visit a landing page, or when they are created manually in the Marketing Cloud Account Engagement database, unless they are also assigned to a user or queue, as explained above. References: [Salesforce Connector], [Sync Prospects with Salesforce]