Read the passage below:
In nineteenth-century maritime commerce, the rapid proliferation of steamship routes across the North Atlantic created unprecedented competition among merchant fleets. To prevent catastrophic price wars that threatened to bankrupt smaller shipping lines, major operators formed cartel-like agreements that checked aggressive rate-cutting. These informal alliances did not eradicate rivalry entirely; rather, they regulated tariff structures so that competition proceeded within predictable bounds. However, when severe economic downturns reduced transatlantic cargo volumes, member lines frequently violated these agreements, proving that voluntary cartels rarely held firm when individual survival was at stake.
In the passage, what word or short phrase most nearly expresses the meaning of the word "checked" as used in the second sentence?
Answer: restrained / curbed / inhibited / controlled / tempered / limited / held in check