Question:
Who was the head of Moscow in Jan, 1991?

Context:
 Yury Luzhkov is the head of the government of Moscow from Jan, 1992 to Jan, 2010. 
 Gavriil Kharitonovich Popov is the head of the government of Moscow from Jan, 1991 to Jan, 1992. 
 Sergey Sobyanin is the head of the government of Moscow from Oct, 2010 to Dec, 2022.

Answer:
Question:
Who was the head of Moscow in Jan, 1991?

Context:
 Yury Luzhkov is the head of the government of Moscow from Jan, 1992 to Jan, 2010. 
 Gavriil Kharitonovich Popov is the head of the government of Moscow from Jan, 1991 to Jan, 1992. 
 Sergey Sobyanin is the head of the government of Moscow from Oct, 2010 to Dec, 2022.

Answer:
user
Gavriil Kharitonovich Popov
assistant
Question:
Who was the head of Moscow in Jan, 1991?

Context:
 Yury Luzhkov is the head of the government of Moscow from Jan, 1992 to Jan, 2010. 
 Gavriil Kharitonovich Popov is the head of the government of Moscow from Jan, 1991 to Jan, 1992. 
 Sergey Sobyanin is the head of the government of Moscow from Oct, 2010 to Dec, 2022.

Answer:
user
Yury Luzhkov
Sergey Sobyanin
assistant
Question:
Who was the head of Moscow in Jan, 1991?

Context:
 Yury Luzhkov is the head of the government of Moscow from Jan, 1992 to Jan, 2010. 
 Gavriil Kharitonovich Popov is the head of the government of Moscow from Jan, 1991 to Jan, 1992. 
 Sergey Sobyanin is the head of the government of Moscow from Oct, 2010 to Dec, 2022.

Answer:
user
Gavriil Kharitonovich Popov
assistant