Which is wrong among the following descriptions of T1 carrier?

A、T1 carrier rates are designed for time division multiplexing of pulse code modulation PCM;

B、T1 system multiplexed 24 channels of digital voice channels on one communication line;

C、PCM encoder alternately inserts 24 channels of 8bit digital voice signals into the designated position in the frame;

D、The data transmission rate of T1 carrier is 2.048 Mbps