A Chart Supplement entry for Pierre Regional Airport (PIR) lists: "COMMUNICATIONS: CTAF 122.7 UNICOM 122.95." Which frequency should a remote pilot monitor for airport advisory traffic at PIR?

Why: The FAA study guide defines the CTAF as the frequency designated for carrying out airport advisory practices, noting it "may be a UNICOM, MULTICOM, FSS, or tower frequency." At PIR, the Chart Supplement entry lists CTAF (122.7) and UNICOM (122.95) as two separate frequencies, and it is the CTAF that serves as the airport's traffic advisory frequency.

• Invents a rule placing UNICOM above CTAF; no such priority exists, and at this airport the two are explicitly separate frequencies with CTAF carrying the advisory role.
• Assumes CTAF and UNICOM are always identical; while the CTAF can be a UNICOM frequency at some airports, the PIR excerpt itself lists different values (122.7 vs. 122.95), showing they can differ.