As Gary Lager puts it, it depends on your closure rate. 3 types of RA advisory will be given:
1. Traffic advisory : "TRAFFIC"
2. Preventive RA : "MONITOR VERTICAL SPEED"
3. Corrective RA : "CLIMB", "DESCEND", "MAINTAIN VERTICAL SPEED MAINTAIN" and "ADJUST VERTICAL SPEED ADJUST".
I haven't heard of any "REDUCE DESCENT" RA.