Final answer:
The Logistics Officer is responsible for securing the portable radios of reserve units and noting their location in the Reserve Log.
Step-by-step explanation:
The individual responsible for reserve units is tasked with ensuring the security and proper documentation of portable radios. From the options provided, it's essential to select the correct pair that accurately fits into the organizational framework of the institution in question. The most likely correct answer would be: C. Logistics Officer, Reserve Log
This answer indicates that the Logistics Officer is the person responsible for placing the reserves' portable radios in a secure location and that the location of these radios must be noted in the front of the Reserve Log. It makes sense that a logistics officer would be responsible for equipment and their respective tracking logs. However, without specific context from an institution's standard operating procedures, this assignment of roles is a general assumption.