What does the 4XX HTTP status code range refer to?

·         Responsive web design·         Independent/standalone mobile site·         Dynamic serving

·         True·         False

·         HTTP·         HTTPS·         FTP

·         The non-critical CSS is required when the site starts to render·         There is an initial view (which is critical)...

·         Invalid mark-up still works, so there’s no need to control it·         Even if GSC says that your mark-up is...

·         rel=amp HTML tags·         hreflang tags·         Canonical tags