Question:
Which political party did Nicola Zingaretti belong to in Aug, 2011?

Context:
 Nicola Zingaretti is a member of the Democratic Party of the Left from Jan, 1991 to Jan, 1998. 
 Nicola Zingaretti is a member of the Democratic Party from Jan, 2007 to Dec, 2022. 
 Nicola Zingaretti is a member of the Democrats of the Left from Jan, 1998 to Jan, 2007.

Answer:
Democratic Party