Honeytokens are decoy credentials or data used to detect data breaches or unauthorized access within a network. Unlike honeypots which are fake systems, honeytokens are specific to data or credentials. The correct answer is Honeytoken because it aligns with the provided description of a monitored fake resource containing seemingly valuable data. Other options like Honeypot or Honeynet, although similar, usually refer to systems or larger network decoys, respectively, not specific pieces of data or credentials. IDS and Firewalls are security measures but not deceptive resources, and a Sinkhole is used for DNS traffic, not data.