Question:
Who was the head coach of the team Brentford F.C. in Dec, 2014?

Context:
 Mark Warburton is the head coach of Brentford F.C. from Dec, 2013 to May, 2015. 
 Thomas Frank is the head coach of Brentford F.C. from Oct, 2018 to Dec, 2022. 
 Dean Smith is the head coach of Brentford F.C. from Nov, 2015 to Oct, 2018.

Answer:
Question:
Who was the head coach of the team Brentford F.C. in Dec, 2014?

Context:
 Mark Warburton is the head coach of Brentford F.C. from Dec, 2013 to May, 2015. 
 Thomas Frank is the head coach of Brentford F.C. from Oct, 2018 to Dec, 2022. 
 Dean Smith is the head coach of Brentford F.C. from Nov, 2015 to Oct, 2018.

Answer:
user
Mark Warburton
assistant
Question:
Who was the head coach of the team Brentford F.C. in Dec, 2014?

Context:
 Mark Warburton is the head coach of Brentford F.C. from Dec, 2013 to May, 2015. 
 Thomas Frank is the head coach of Brentford F.C. from Oct, 2018 to Dec, 2022. 
 Dean Smith is the head coach of Brentford F.C. from Nov, 2015 to Oct, 2018.

Answer:
user
Thomas Frank
Dean Smith
assistant
Question:
Who was the head coach of the team Brentford F.C. in Dec, 2014?

Context:
 Mark Warburton is the head coach of Brentford F.C. from Dec, 2013 to May, 2015. 
 Thomas Frank is the head coach of Brentford F.C. from Oct, 2018 to Dec, 2022. 
 Dean Smith is the head coach of Brentford F.C. from Nov, 2015 to Oct, 2018.

Answer:
user
Mark Warburton
assistant