MDL-27122 admin Improved block protection help string

lang/en/admin.php

@@ -72,7 +72,7 @@
 $string['blockinstances'] = 'Instances';
 $string['blockmultiple'] = 'Multiple';
 $string['blockprotect'] = 'Protect from delete';
-$string['blockprotect_help'] = 'The blocks instances will be protected from deletion from the site-wide context, and this is primarily used to protect the navigation and settings blocks which can be very hard to get back if accidentally delete.';
+$string['blockprotect_help'] = 'Selected block instances will be protected from deletion from the site-wide context. This is primarily used to protect the navigation and settings blocks which can be very hard to get back if accidentally deleted.';
 $string['blockunprotect'] = 'Unprotect';
 $string['blocksettings'] = 'Manage blocks';
 $string['bloglevel'] = 'Blog visibility';