Answer:
C). An increase in wind speed and a decrease in precipitation.
Explanation:
A thunderstorm is characterized as a storm that consists of thunder and lightning produced by cumulonimbus(a cloud with a tall structure and flat base) usually accompanied with heavy rain, strong winds, hails sometimes as well. Thus, the weather conditions that would most likely occur during a thunderstorm would be 'an increase in wind speed and a decrease in precipitation' and low air pressure. Thus, option C is the correct answer.
