Sam Is Auditing a Web Application for SQL Injection Vulnerabilities

Sam is auditing a web application for SQL injection vulnerabilities. During the testing, Sam discovered that the web application is vulnerable to SQL injection. He starts fuzzing the search field in the web application with UNION based SQL queries, however, he realized that the underlying WAF is blocking the requests. To avoid this, Sam is trying the following query: UNION/**/SELECT/**/'/**/OR/**/1/**/=/**/1 Which of the following evasion techniques is Sam using?

A) Sam is using char encoding to bypass WAF
B) Sam is using obfuscated code to bypass WAF
C) Sam is using inline comments to bypass WAF
D) Sam is manipulating white spaces to bypass WAF