When signal strength is poor, mobile devices constantly boost their transmission power in an attempt to maintain a stable connection. This results in dropped calls/data and rapid battery drain. Since a repeater was installed, misalignment or misconfiguration could be degrading the signal strength.

A. WPS applies to Wi-Fi, not cellular repeaters.

C. Channel frequency might matter for interference, but signal strength is the most direct cause of the described symptoms.

D. Power budget applies to PoE and wired devices, not mobile phones.

References (CompTIA Network+ N10-009):

Domain: Network Troubleshooting — Wireless/cellular troubleshooting, signal strength impact, user symptoms (battery drain, poor connectivity).