What is a recommended way to migrate data from an external system while ensuring that the data adheres to data quality rules established for the Salesforce org?

What is a recommended way to migrate data from an external system while ensuring that the data adheres to data quality rules established for the Salesforce org?
A . Cleanse the data outside of Satesfbrce and then migrate the data.
B . Use the Salesforce data loader to load and cleanse the data.
C . Use the Salesforce import wizard to load and cleanse the data.
D . Upload the data into Salesforce and then run data cleansing tools.

Answer: A