Which type of data skew occurs when too many child records are tied to a single parent record?

Account data skew refers to the situation in Salesforce where a large number of child records are related to a single parent record, specifically under the Account object. This type of data skew can impact system performance and may cause issues with operations like data sharing, reporting, and maintenance, particularly in organizations with a high volume of child records. When many child records are associated with a single account, it can lead to challenges in data management, such as hitting limits on the number of records displayed or processed in user interfaces.

In contrast, the other types of data skew involve different scenarios. Ownership skew typically refers to a situation where a single user owns a disproportionate number of records, impacting sharing and performance. Lookup skew relates to situations involving excessive relationships between individual parent and child records that can cause similar performance issues, but not specifically tied to the Account object. Custom data skew isn’t a recognized category in the context of Salesforce, which is why it doesn't apply here.

Understanding account data skew is crucial for maintaining system performance and ensuring optimal usage of Salesforce, making this the correct choice in identifying the type of data skew related to numerous child records linked to a single parent record.