A Watering Hole Attack is characterized by attackers planting malware on websites or services that are commonly accessed by their intended victims. The goal is to infect users who visit these trusted sites by injecting malicious code or malware. This type of attack leverages the trust users place in frequently visited services to deliver malware covertly.

Other options like Remote Access Trojans, Phishing, and Exploit Kits are attack types but do not specifically involve compromising commonly accessed services to plant malware.