Question:
Who was the chair of Federal Office for Information Security in Nov, 1991?

Context:
 Udo Helmbrecht is the chair of Federal Office for Information Security from Mar, 2003 to Jan, 2009. 
 Michael Hange is the chair of Federal Office for Information Security from Oct, 2009 to Dec, 2015. 
 Otto Leiberich is the chair of Federal Office for Information Security from Jan, 1991 to Jan, 1992. 
 Arne Schönbohm is the chair of Federal Office for Information Security from Feb, 2016 to Oct, 2022.

Answer:
Question:
Who was the chair of Federal Office for Information Security in Nov, 1991?

Context:
 Udo Helmbrecht is the chair of Federal Office for Information Security from Mar, 2003 to Jan, 2009. 
 Michael Hange is the chair of Federal Office for Information Security from Oct, 2009 to Dec, 2015. 
 Otto Leiberich is the chair of Federal Office for Information Security from Jan, 1991 to Jan, 1992. 
 Arne Schönbohm is the chair of Federal Office for Information Security from Feb, 2016 to Oct, 2022.

Answer:
user
Otto Leiberich
assistant
Question:
Who was the chair of Federal Office for Information Security in Nov, 1991?

Context:
 Udo Helmbrecht is the chair of Federal Office for Information Security from Mar, 2003 to Jan, 2009. 
 Michael Hange is the chair of Federal Office for Information Security from Oct, 2009 to Dec, 2015. 
 Otto Leiberich is the chair of Federal Office for Information Security from Jan, 1991 to Jan, 1992. 
 Arne Schönbohm is the chair of Federal Office for Information Security from Feb, 2016 to Oct, 2022.

Answer:
user
Udo Helmbrecht
Arne Schönbohm
Michael Hange
assistant
Question:
Who was the chair of Federal Office for Information Security in Nov, 1991?

Context:
 Udo Helmbrecht is the chair of Federal Office for Information Security from Mar, 2003 to Jan, 2009. 
 Michael Hange is the chair of Federal Office for Information Security from Oct, 2009 to Dec, 2015. 
 Otto Leiberich is the chair of Federal Office for Information Security from Jan, 1991 to Jan, 1992. 
 Arne Schönbohm is the chair of Federal Office for Information Security from Feb, 2016 to Oct, 2022.

Answer:
user
Otto Leiberich
assistant