This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.
Q: Passage: The government broadened land ownership by returning land that had been sold to large landowners in the late Ming period by families unable to pay the land tax. To give people more incentives to participate in the market, they reduced the tax burden in comparison with the late Ming, and replaced the corvee system with a head tax used to hire laborers. The administration of the Grand Canal was made more efficient, and transport opened to private merchants. A system of monitoring grain prices eliminated severe shortages, and enabled the price of rice to rise slowly and smoothly through the 18th century. Wary of the power of wealthy merchants, Qing rulers limited their trading licenses and usually refused them permission to open new mines, except in poor areas. These restrictions on domestic resource exploration, as well as on foreign trade, are held by some scholars as a cause of the Great Divergence, by which the Western world overtook China economically. Question: What happened to the price of rice during the 18th century?
A:
rise slowly and smoothly