Which MAC should be used: device MAC or Interface MAC?

        My L3 switch has ~30 interfaces. If you look at the output below there are two MAC addresses showing in the results of the <code>show interface</code> command. The hardware address is the same for all interfaces. The physical address is different for each interface.
Assume that an IP address was configured on interface ce1/1. When ce1/1 receives an ARP request for the IP configured on it, which MAC should be used in the ARP reply? What are the potential issues if I use the hardware address rather than the physical interface address? Is there any standard talking about this situation?
rtr1#sh interface
Interface ce1/1
  Scope: both
  Flexport: Breakout Control Port (Active): Break Out Enabled
  Hardware is ETH  Current HW addr: 4c76.2541.a6c1
  Physical:4c76.2541.a6f2  Logical:(not set)

  Interface ce1/2
  Scope: both
  Flexport: Non Control Port (Active)
  Hardware is ETH  Current HW addr: 4c76.2541.a6c1
  Physical:4c76.2541.a6f3  Logical:(not set)

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