The correct answer is C. Use FortiWebCloud.

FortiWebCloud is a SaaS cloud-based web application firewall (WAF) that protects public cloud hosted web applications from the OWASP Top 10, zero day threats, and other application layer attacks1. FortiWebCloud also includes robust features such as API discovery and protection, bot mitigation, threat analytics, and advanced reporting2. FortiWebCloud supports multiple regions across the world, and you can choose the region that is closest to your applications to minimize traffic cost3.

The other options are incorrect because:

FortiADC is an application delivery controller that provides load balancing, acceleration, and security for web applications. It is not a dedicated WAF solution and does not offer the same level of protection as FortiWebCloud4.

FortiCNP is a cloud-native platform that provides security and visibility for containerized applications. It is not a WAF solution and does not protect web applications from the OWASP Top 10 vulnerabilities5.

FortiGate is a next-generation firewall (NGFW) that provides network security and threat prevention. It is not a WAF solution and does not offer the same level of protection as FortiWebCloud for web applications. It also requires additional configuration and management to deploy in the public cloud6.

1: Overview | FortiWeb Cloud 23.3.0 - Fortinet Documentation 2: Web Application Firewall (WAF) & API Protection | Fortinet 3: [FortiWeb Cloud WAF-as-a-Service | Fortinet] 4: [Application Delivery Controller (ADC) | Fortinet] 5: [Fortinet Cloud Native Platform | Fortinet] 6: [FortiGate Next-Generation Firewall (NGFW) | Fortinet]