Option A is not a main WAF function . Huawei Cloud Web Application Firewall is an application-layer web protection service . It analyzes HTTP and HTTPS traffic and protects websites against threats such as SQL injection, cross-site scripting, command injection, malicious bots, scanners, CC attacks, and other web exploits.

Huawei explicitly lists information leakage prevention , web tamper protection , and anti-crawler protection among WAF's protection functions. Information leakage prevention can mask or block sensitive information such as ID numbers, phone numbers, and email addresses. Web tamper protection prevents unauthorized modification of protected static website pages. Anti-crawler protection identifies and mitigates malicious automated crawler behavior.

Brute-force attacks against ECS operating-system or application accounts , however, fall primarily under Host Security Service (HSS) . Huawei documents HSS detection and blocking capabilities for brute-force attacks involving services such as SSH, RDP, MySQL, SQL Server, and FTP.

WAF can mitigate certain web-based authentication abuse using web rules and rate controls, but generic ECS account brute-force protection is not the WAF function described here.

Therefore, the required answer is A .

Reference topics: Web Application Firewall; Information Leakage Prevention; Web Tamper Protection; Anti-Crawler; Host Security Service.

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