This is the 307th most frequent Finnish word.
valittiin
"Valittiin" means "was chosen" or "were selected" in English.
In this sentence, 'valittiin' is the past passive form of 'valita' (meaning 'to choose'), indicating that the subject (her/him) was chosen, and the action was performed by unspecified others.
Hänet valittiin joukkueen kapteeniksi.
They were chosen as the team captain.
Here, 'valittiin' operates as the past passive form, referring to the action of selecting being done to the top three works.
Kilpailussa valittiin kolme parasta työtä jatkoon.
In the competition, three best pieces were selected to proceed.
'Valittiin' acts as the past passive, pointing to the selection of a new chairman during the meeting.