What does the Digit Discard Instruction ofPreDotdo to the pattern 9.2148134444?
A.
prefix a 9 before the “-” if none is dialled
B.
discard 2148134444 and send the 9 access code
C.
only collect the first four digits counting right to left.
D.
change it to 2148134444 before presenting it to the PSTN