Which of the following is a common OSI Layer 3 (network layer) troubleshooting issue? (Choose two.)

A) Mismatched maximum transmission unit (MTU) for IP packets
B) Distance limitations exceeded
C) Incorrect subnet mask
D) Crosstalk
E) Layer 2 loop

A, C
Explanation: Mismatched maximum transmission unit (MTU) for IP and incorrect subnet mask are OSI Layer 3 (physical layer) troubleshooting issues. Distance limitations exceeded and crosstalk are OSI Layer 1 (physical layer) troubleshooting issues, and Layer 2 loop is an OSI Layer 2 (data link layer) troubleshooting issue.
Mismatched maximum transmission unit (MTU) for IP and incorrect subnet mask are OSI Layer 3 (physical layer) troubleshooting issues. Distance limitations exceeded and crosstalk are OSI Layer 1 (physical layer) troubleshooting issues, and Layer 2 loop is an OSI Layer 2 (data link layer) troubleshooting issue.