How to choose function set for Xbee3 Mesh kit

I have a Digi Xbee3 Zigbee Mesh kit of 3 devices. I want to make a mesh network (2 as end devices, 1 as a coordinator).

Out of the available 3 function sets(Digimesh 2.4, 802.15.4, Zigbee), which one would suit my purpose ?

Thanks in advance.