URL Filtering remains a core first line of web defense even in a cloud and HTTPS-heavy world. It controls access by category, risk, and destination before deeper controls such as DLP, sandboxing, or isolation are applied. TLS inspection improves visibility; it does not make URL Filtering obsolete. Option A (URL Filter is the most commonly used web filtering technique in the arsenal. It acts as first line of defense) is correct because URL Filtering is still a commonly used first-line web-filtering control.
Why the other options are incorrect:
B. In a modern cloud world, access to all Internet sites and cloud applications should be granted by default. URL Filtering is no longer needed: URL Filtering controls web destinations by category, URL, risk, and action such as allow, block, caution, or isolate.
C. URL Filtering has been replaced by CASB functionality through blocking access to all Internet sites and only allowing a few corporate applications: Out-of-band CASB works through SaaS APIs to inspect or remediate content already sitting inside cloud applications.
D. URL Filtering is outdated and no longer needed. The rise of HTTPS leads renders URL Filtering ineffective as all traffic is encrypted: URL Filtering controls web destinations by category, URL, risk, and action such as allow, block, caution, or isolate.
