Given the following routing table
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface 192.168.178.0 0.0.0.0 255.255.255.0 U 9 0 0 wlan0
Why does the command route add default gw 192.168.1.1 fail?
A. Because there is no route to 192.168.1.1.
B. Because only one route can exist at a time.
C. Because there is already a default route.
D. Because default routes can not be set manually.
E. Because default routes must be set with ifconfig.