Strange, it looks like a recent Kartris, I double checked the maindata setup script in the repo, it shows four options:
INSERT [dbo].[tblKartrisConfig] ([CFG_Name], [CFG_Value], [CFG_DataType], [CFG_DisplayType], [CFG_DisplayInfo], [CFG_Description], [CFG_VersionAdded], [CFG_DefaultValue], [CFG_Important]) VALUES (N'general.security.ssl', N'n', N's', N'b', N'y|n|a|e', N'y = SSL on for essential pages, n = SSL off, a = SSL always on for all pages, e = external SSL (such as Cloudflare)', 1, N'n', 0)
Did you upgrade this site from an older version? There were originally only two options, but quite a long time ago. And pretty sure the upgrade scripts also upgrade this setting to add the extra version.