$1.$ In a manufacturing plant, a worker was operating a machine that was used for cutting metal parts. The worker was attempting to adjust the machine's settings when his hand became caught in the machine's moving parts. Based on the aforementioned case: $($a$)$ Describe the MOST appropriate guarding in isolating the machinery hazard. $($b$)$ Identify the OSH legal requirement pertaining to machinery safety. $($c$)$ Discuss how to ensure safety in machinery operation.