Title says it all.
I'm going with B. For the value of the picks, you can't criticize Marvin. Leon Hall, Jonathan Joseph, and Madieu Williams is going to make up a very lights out secondary hopefully by the end of the year. I wasn't too thrilled with the Irons pick at first, but with the average lifespan of running backs in the league, it may be time to consider life after Rudi. However, I think Ahmad Brooks in the third round is better than anybody who was available at that time.
While I give all the praise, the Bengals did not address the front seven until the seventh round unless you count Ahmad Brooks, and he was there last year. The team will be significantly better next year because of the schedule, but as Cedric said in the NFL Draft thread, they will not win many games in the playoffs.
A for the value of the picks, C for not filling needs.