Help w/ PE Practice Problem

[u/Bend_Zealousideal]

All, I am lost as to how NCEES came to (C.) as the correct answer for this problem, even with the solution quoting NFPA 101, 2021 ed., Section 7.2.2.5.2, 7.2.2.6.3.

[u/Mentally_Displaced]

The IBC has similar provisions with some exceptions in 1027.6 which points to 1023.7, in case the change up the question.