Northern Trail Outfitters held an event for hikers to blaze the trail for the new year. Their marketing team collected over a million new lead records to upload into Salesforce. What is the…

Lightning Sync is used for syncing contacts, events, and tasks between Salesforce and Microsoft® Exchange or Google, not for mass data uploads of lead records.

While an AppExchange app could potentially handle large data uploads, Data Loader is Salesforce's native, built-in solution for such tasks and is generally preferred for direct bulk operations.

The Data Import Wizard is suitable for importing up to 50,000 records at a time and provides a user-friendly interface, but it is not designed for the volume of 'over a million' records mentioned.

Data Loader is a powerful client application designed for inserting, updating, upserting, deleting, or exporting large amounts of data (up to 5 million records) in a single operation. Its capacity to handle over a million records makes it the ideal choice for this scenario.