Harry, a professional hacker, targets the IT infrastructure of an organization. After preparing for the attack, he attempts to enter the target network using techniques such as sending spear-phishing emails and exploiting vulnerabilities on publicly available servers. Using these techniques, he successfully deployed malware on the target system to establish an outbound connection.
What is the APT lifecycle phase that Harry is currently executing?

A. Initial intrusion
B. Persistence
C. Cleanup
D. Preparation