Which of the following descriptions about electrical layer scheduling is wrong?

Which of the following descriptions about electrical layer scheduling is wrong?
A . Inter-board cross-connect refers to the cross-connect configured between different boards. Inter-board cross-connection dispatches ODUk services between boards in a subrack through the backplane and centralized cross-connection boards.
B. Intra-board cross-connect refers to the cross-connect configured between different ports on the same board.
C. TTA and TDC boards support aggregation mode and non-aggregation mode.
D. In the aggregation mode application scenario, it is necessary to cross within the board first, and then cross between boards.
E. All cross-connects need to be configured on the network management system.

Answer: C