Secure Views in Snowflake are specifically designed for data privacy and security, particularly when data is being shared across different business units or external accounts. The primary benefit of a secure view is that it prevents users from seeing the internal definitions (the underlying SQL) and protects against "trial-and-error" data discovery.

In a standard view, a savvy user might be able to deduce information about data they are not authorized to see by observing the query optimizer's behavior or by looking at the query profile. For example, by using specific filters or functions, a user might observe how long a query takes to execute or check the statistics to guess the distribution of values in hidden columns. Secure views prevent this by ensuring that Snowflake does not expose the internal metadata or the specific row/column counts that would allow a user to make observations about the quantity or nature of the underlying data that falls outside their access privileges.

Evaluating the Options:

Option B and C are incorrect because Snowflake does not merely obfuscate bytes or micro-partitions in a way that suggests a simple "hiding" of metrics; it fundamentally changes the query plan generation to ensure security.

Option D is a common misconception. In fact, secure views can sometimes be less performant than regular views. This is because the Snowflake optimizer is restricted from using certain optimizations (like predicate pushdown) that might inadvertently reveal data patterns to an unauthorized user.

Option A is the 100% correct answer. The "secure" nature of the view ensures that the user cannot use statistical side-channels or metadata observations to infer the existence or volume of data they are restricted from seeing.