There is no batch delete in Respondus 4 to avoid accidental deletion of too many questions without any means of recovery.

The recommended method to "remove" a large number of questions at a time is to use the Respondus 4 Exam Wizard or the Respondus->Edit->"Copy from Another File" to copy the questions for keeping into a new file, leaving the "unwanted" question in the old file. After creating a new file of questions, one can keep the old file for archive purposes or delete the old file.