What happens if an object that enters as a copy has abilities that replace the enters-the-battlefield event?

When an object enters the battlefield as a copy of another permanent, it replicates not just the card's characteristics—such as its name, mana cost, and power and toughness—but also any triggered or replacement abilities associated with that object. If the object has abilities that are designed to replace the enters-the-battlefield event, those abilities will indeed take effect.

For instance, if a permanent has an ability that states "When this creature enters the battlefield, create a token," and another object enters as a copy of it, the copy will still trigger this ability upon entering the battlefield and create the token. Similarly, if there are replacement effects that modify how the object enters the battlefield, those will be applied as well.

This adherence to copying the original object's abilities ensures that the game maintains consistent interactions and complexity. Therefore, the correct option reinforces the fundamental concept of copying in Magic: The Gathering, where the duplicated object retains all relevant abilities it should have.