Cat C can NOT sign for a daily or weekly. They can however sign for A-Checks, which can also be performed by Line Maint personnel. In other words, depending on the company's structure, you can have a certain amount of B1, B2 staff certifying the several tasks from the A-Check, and in the end you may or not need to have a C cat signing off the Check. As long as the individual tasks were independently written in the LB, you don't need a C to certify.
On the other hand, you may have those individual tasks grouped in a package (internal protocol) and then you DO need a C cat cert. staff to sign off the A-Check.
But I think daily and weekly checks are out of the C scope.
As for the A cat, he can sign off is own work, as long as it does not involve troubleshooting (tasks involving less than 10 steps may not qualify for T/S scope)
