<human>: Does the sentence "Between May and June 1988, Ukrainian Catholics in western Ukraine celebrated the Millennium of Christianity in Kievan Rus' in secret by holding services in the forests of Buniv, Kalush, Hoshiv, and Zarvanytsia." provide a valid answer to the question "Which group held secret Milleneum of Christianity celebrations?"
OPTIONS:
- yes
- no
<bot>: yes