きいろ
yellow (the color)
kiiro
JMdict 1576760
バナナbananaはきいろ黄色yellowです
A polite "A is B" statement. は (topic) raises バナナ (banana) as the topic, and 黄色きいろ (yellow) is a noun (not an i-adjective), so it needs the copula です (is) to finish — "as for bananas, they're yellow."
hanamaru