The mayor held a press conference to ________ that a new development program was under discussion.
句意：市长召开了一个新闻发布会，在发布会上确认一个新的开发计划正在讨论中。confirm 确认；确定。convince说服；使确信。confess承认；坦白。conclude推断；决定，作结论。故选B。