A vessel obtains a single line of position at 0800 and is unable to obtain a simultaneous second LOP. She advances the 0800 LOP along the DR track and crosses it with a new LOP taken at 0830. The resulting position is properly termed a:

Why B is correct

Bowditch Ch. 7 §702 defines a running fix as a fix obtained when LOPs cannot be taken simultaneously, where the first LOP is advanced along the DR track to the time of the second observation and the intersection constitutes the running fix, which is less accurate than a fix from simultaneous LOPs.