What switch configuration will correct this problem?

The AP is unable to join the WLC.

What switch configuration will correct this problem?
A . interface vlanl
ip helper-address 10.10.10.10
B . interface vlan20
ip helper-address 10.10.10.10
C . ipdhcp pool vlanl
option 43 ascii ‘10.10.10.10’
D . ip dhcp pool vlan20
option 43 ascii ‘10.10.10.10’
E . ipdhcp pool vlanl
option 43 hex f1040a0a0a0a
F . ip dhcp pool vlan20
option 43 hex f1040a0a0a0a