You fail to establish a Site-to-Site VPN connection between your company’s main office and an Azure virtual network.

You need to troubleshoot what prevents you from establishing the IPsec tunnel.

Which diagnostic log should you review?

A. IKEDiagnosticLog

B. RouteDiagnosticLog

C. GatewayDiagnosticLog

D. TunnelDiagnosticLog

Reference:
https://docs.microsoft.com/en-us/azure/vpn-gateway/troubleshoot-vpn-with-azure-diagnostics