Which religion has shaped European and German culture?

EDITORIAL LEARNING AID

Why is this answer correct?

Christianity has shaped European and German culture over centuries, for example in art, music, architecture, the calendar and public holidays. Hinduism (a), Buddhism (c) and Islam (d) originate in other regions and have not shaped this culture in a comparable way.

Christianity shaped Europe: holidays, art, calendar.

This translation and explanation are editorial learning aids. The official German wording and answer key govern the examination.