The correct answer is A: Plus or minus 5 MHz. According to standard 70-centimeter band plans, the common repeater frequency offset is 5 MHz. This is much larger than the 2-meter offset because the 70-centimeter band is wider (420-450 MHz, a 30 MHz range). The 5 MHz offset provides good separation between repeater input and output frequencies, preventing interference. For example, a repeater might receive on 442.000 MHz and transmit on 447.000 MHz (5 MHz higher, or +5 MHz). Or it might receive on 447.000 MHz and transmit on 442.000 MHz (5 MHz lower, or -5 MHz). This 5 MHz offset is standard for 70-centimeter repeaters.