Which Is the Best Counterexample to the Principle in the Following

Which is the best counterexample to the principle in the following Argument from Principle?
[Pay attention to the criteria for good counterexamples from Chapter 6 of Doing Practical Ethics.]
1) There's nothing wrong with using other people's property as long as your use doesn't cause them any unhappiness.
2) Using your neighbor's wi-fi internet without their permission doesn't cause them any unhappiness.
So, it's not wrong to use your neighbor's wi-fi without their permission.

A) Suppose that an FBI agent is chasing a domestic terrorist from a white supremacist group. The terrorist has hidden a bomb in someone's car, and the FBI agent has just figured this out. The agent doesn't have time to ask the car's owner if they can use the car. So, without the owner's permission, the agent drives the car away to a bomb disposal unit. Clearly, it's not wrong for the agent to do this.
B) Imagine a person uses a computer program to take small amounts of money out of millions of people's bank accounts and funnels them into their own account. In this way, they steal lots of money, but the people stolen from don't notice and so aren't unhappy at all. Still, stealing in this way is wrong.
C) Suppose someone downloads a musical album illegally and without the artist's permission through an illegal website. Suppose the artist finds out. This would clearly make it wrong to download the album illegally.
D) It's always wrong to use other people's stuff without their permission. Everyone knows that.