Write a trigger with its test class for only system admin user should be able to delete the task.
....Trigger.... trigger DeleteCheck on Task (before delete) { Id profileid=Userinfo.getProfileId(); profile profilname=[select Name from Profile where id=:profileid]; for(Task accountDuplicate:Trigger.old) { if(profilname.Name!='System Administrator') { accountDuplicate.addError('No Access for Deletion'); } } } . ...Test Class.... @istest public class DeleteCheckTest { @istest static void TestAccountTrigger(){ Task Tcc = new Task(); Tcc.Subject = 'Email'; Tcc.Priority = 'Low'; Tcc.Status = 'in progress'; insert Tcc; Id profileid=Userinfo.getProfileId(); profile profilname=[select Name from Profile where id=:pro...