What happens to the emp object's properties after calling Object.seal?

When the Object.seal method is called on an object, such as the emp object, it restricts the ability to change the structure of the object. Specifically, all existing properties of the object become non-configurable, meaning that their configuration cannot be changed. This means that you can't delete properties or change their configurability.

While properties can still be modified (assuming they are writable), no new properties can be added, nor can existing properties be removed or reconfigured. The key point here is that sealing the object ensures the integrity of its structure and prevents any changes to whether properties can be deleted or modified.

Thus, saying that all properties are made non-configurable captures the essential effect of the seal method accurately, making this the correct answer.