The book ends with God’s question comparing Jonah’s pity for the plant with God’s concern for Nineveh. God mentions the city’s many people who “do not know their right hand from their left,” and also “much cattle” Jonah 4:10–11. The story closes without recording Jonah’s reply Jonah 4:11.
In Jonah 4:9–11, God confronts Jonah’s anger over a plant that withered. Jonah insists his anger is justified, even fatal. God then contrasts Jonah’s concern for something he neither made nor sustained, something brief and fragile, with God’s concern for Nineveh, a vast city full of people who lack basic discernment and even animals. This is the closing exchange of the book and comes after Jonah has preached to Nineveh and the city has responded, leading God to withhold the threatened disaster (Jonah.3.10). Jonah then reacts with displeasure and anger, and God already challenged him once about whether his anger is appropriate (Jonah.4.4).
The passage closes with God questioning Jonah’s anger over a plant and then turning that moment into a comparison. Jonah admits he is intensely angry and insists he is “right” to feel that way. God highlights that Jonah “cared” (or had pity/concern) for something he did not make, did not work for, and could not keep alive.
A careful answer keeps the immediate passage, the book's argument, and the whole-Bible storyline together, so the question is answered in context instead of as a detached idea.
Start with Jonah 4:10-11, then read the surrounding section so the answer stays connected to the passage's flow.
10Yahweh said, "You have been concerned for the vine, for which you have not labored, neither made it grow; which came up in a night, and perished in a night.
11Shouldn`t I be concerned for Nineveh, that great city, in which are more than one hundred twenty thousand persons who can`t discern between their right hand and their left hand; and also much cattle?"