Rs$,$R$,$Rc in the network below represent the corresponding bandwidth of each link assuming the bandwidth R is equally share between the three connections $.$ if Rs$=80$Mbps $,$R$=100$Mbps $,$ and Rc$=40$Mbps then the end to end throughput for a client server connection is :

a$.10Mbps.$

b$.20Mbps.$

c$.25Mbps.$

d$.40Mbps.$

e$.$ None of the above.