Which is the correct description of enharmonic tie?

A、The 2nd note in the enharmonic tie does not need to be played;
B、The 2nd note needs to be played once again;
C、The 2nd note in the enharmonic tie needs to be played again, with no need to maintain the duration of the 1st;
D、The 2nd note of the enharmonic tie does not need to be played, with the duration of the 1st maintained until the end of the 2nd.