“From the Chinese government’s perspective, I think it would be likely that it would target sectors that have political resonance in the United States,” he said.

China imported $21.4 billion in American agricultural products in 2016, according to government data, more than half of which was soybeans.

“Agriculture affects a sector where the United States enjoys a surplus and where there are competitors in other parts of the world for the commodities that China imports,” Mr. Ross said. “And the producers are predominantly in states which voted for President Trump.”

He noted that Boeing, the aircraft maker, would be “another obvious example” of a company that could be in Beijing’s cross-hairs if the Trump administration imposes trade sanctions against China.

Boeing competes against Airbus of Europe to sell jetliners to Chinese carriers. This month, President Emmanuel Macron of France said on a visit to China that an $18 billion contract with it for 184 Airbus A320 narrow-body jets would be finalized soon, according to Reuters.

Yukui Wang, a spokesman for Boeing, declined to comment.

China could also consider initiating antidumping investigations of American imports of other products, contending that they are sold below their fair value and subsidized by the United States, Mr. Ross said.

China remains an important market for some of the largest corporations in the United States, and their fortunes are tied in part to the Chinese authorities’ willingness to let them sell products or operate businesses there. That has made them fearful of complaining publicly about lack of market access and other regulatory problems. Their worries include being subject to unannounced government audits or facing antimonopoly investigations.