Answer: d. stock prices of U.S. nuclear plants increased.
Step-by-step explanation:
Chernobyl was a nuclear power plant in the former Soviet Union that was being used to produce electricity until it suffered a meltdown that effectively rendered the surrounding areas unlivable.
In response to this disaster, the stock prices of U.S. nuclear power plants went up because the Soviet meltdown not only reduced the supply of nuclear powered electricity but also showed that American engineering was superior and so people bought more American nuclear plant shares which took its price up.