This question has similarities with other questions. Be careful to understand exactly what it is asking...

• Accountable Manager: Holds ultimate responsibility and authority for the safety and compliance of the operator.
• Safety Manager: Manages the day to day operation and effectiveness of the operator's Safety Management System (SMS).

Here we are asked who would be the post-holder responsible for the Flight Data Monitoring (FDM) programme. This is describing the safety manager. The safety manager is responsible for the day-to-day running of the SMS safety management system, which includes FDM.

For a smaller operator (Non complex) this is typically the accountable manager or a line Captain. Both of these positions offer sufficient relevant experience in operational roles to be an effective safety manager.

For a larger operator (Complex) this position would now need a more dedicated specialist due to the size or type of operation. Now the operator will need a safety manager and safety review board.

EASA AIR OPS
Regulation (EU) 2015/1329
ORO.AOC.130 Flight data monitoring – aeroplanes

(a) The operator shall establish and maintain a flight data monitoring programme, which shall be integrated in its management system, for aeroplanes with a maximum certificated take-off mass of more than 27 000 kg.
(b) The flight data monitoring programme shall be non-punitive and contain adequate safeguards to protect the source(s) of the data.

AMC1 ORO.AOC.130 Flight data monitoring – aeroplanes
FLIGHT DATA MONITORING (FDM) PROGRAMME

(a) The safety manager, as defined under AMC1-ORO.GEN.200(a)(1), should be responsible for the identification and assessment of issues and their transmission to the manager(s) responsible for the process(es) concerned. The latter should be responsible for taking appropriate and practicable safety action within a reasonable period of time that reflects the severity of the issue.