John works as a professional Ethical Hacker. He has been assigned the project of testing the security of www.we-are-secure.com. He has successfully performed the following steps of the preattack phase to check the security of the We-are-secure network:

- Gathering information
- Determining the network range
- Identifying active systems

Now, he wants to find the open ports and applications running on the network.

Which of the following tools will he use to accomplish his task?