An Ethernet switch has eight ports and all ports must be operational for 24 hours, from Monday through Friday. However, a failure of Port4 occurs as follows:
• Monday = 8 PM to 9 PM
• Wednesday 7 PM to 9 PM
• Thursday = 6 AM to 9 AM
• Saturday = 4 PM to 7 PM
What is the MTTR of Port 4?
A. 2 hours
B. 3 hours
C. 28 hours
D. 38 hours