Question:
Who was the chair of Mánes Union of Fine Arts in Oct, 1890?

Context:
 Ivan Exner is the chair of Mánes Union of Fine Arts from Jan, 2015 to Dec, 2022. 
 Jiří T. Kotalík is the chair of Mánes Union of Fine Arts from Jan, 2008 to Jan, 2009. 
 Adam Hoffmeister is the chair of Mánes Union of Fine Arts from Jan, 2013 to Jan, 2015. 
 Mikoláš Aleš is the chair of Mánes Union of Fine Arts from Jan, 1887 to Jan, 1896.

Answer:
Mikoláš Aleš