087F B
 "SITOR" communications are based on a digital code system:
a) Consisting of 7 bits, with four ones and three zeros.
b) Consisting of 7 bits, with four zeros and three ones.
c) Consisting of 5 bits TELEX and 8 bits Fax. 
d) Consisting of 5 bits for ship stations and 7 bits for shore stations.
