Which One of the Following Is the Best Example of Inert

Which one of the following is the best example of inert knowledge?

A) Kate is surprised to learn that Winston Churchill, Great Britain's prime minister during World War II, lost his battle for reelection in 1945.
B) Wally knows how to multiply and divide fractions but doesn't realize he can use this knowledge when he needs to adjust measurements in a cake recipe.
C) In his everyday speech, Quincy correctly uses irregular verbs (e.g., go, went, have gone) , but he can't explain the difference between regular and irregular verbs.
D) After breaking her leg, Paisley is unable to play basketball for several months.