School billboard. Allon

A school billboard is a large board that displays information. In Hausa, this is “allon nuna makaranta.” The word “nuna” means to show or display.

The other options focus on writing or announcements. But a billboard is about displaying things, not just writing. It shows pictures and information to everyone.

The word “nuna” captures the display purpose of a billboard. This is why it is the correct choice.