default or selected kernelversion does not have config value CONFIG_IP_ROUTE_MULTIPATH_WRANDOM.
Result is shown for kernelversion 5.4.123

MULTIPATH: weighted random algorithm

modulename: multipath_wrandom.ko

configname: CONFIG_IP_ROUTE_MULTIPATH_WRANDOM

Linux Kernel Configuration
└─>Networking support
└─>Networking options
└─>MULTIPATH: weighted random algorithm
In linux kernel since version 2.6.12  
Multipath routes are chosen in a weighted random fashion.
The per route weights are the weights visible via ip route 2. As the
corresponding state management introduces some overhead routing delay
is increased.

source code: