Which of the following is an example of an installation a) writers performing their poems on a public stage b) people getting together in a cafe to share poetry c) a collection of poems in a literary magazine d) a poem appearing on a banner inside a city bus

The correct option would be option D, a poem appearing on a banner inside a city bus. Installation art refers to large-scale mixed media constructions often designed for a specific place in order to transform it for a temporary period of time. Option A would be an artistic performance. Option B could be considered a happening, and option C, would be an editor's choice to publish some poems in a literary magazine.