Which of the following is a technique used by attackers to make a message difficult...

Obfuscation is a technique used to make data or code difficult to understand. It is often employed by attackers to conceal the true intent of their code or communications, making it harder for security professionals, automated tools, and others to analyze or detect malicious activity. Obfuscation can involve the use of ambiguous or misleading language, as well as more technical methods such as encoding, encryption, or the use of nonsensical variable names in source code to hide its true functionality.

References:The CREST CPTIA program discusses various techniques attackers use to evade detection, including obfuscation, highlighting how it complicates the analysis and understanding of malicious payloads.