Which interesting fact about dickens' life could most directly apply to the manner in which he constructed the plot in his story the signalman?

a. he worked in a factory as a child.
b. at one point in his life, he wrote humorous sketches of everyday life in london, england.
c. he was a law clerk at fifteen years of age.
d. when he first began writing professionally, his pay was based on the number of words he wrote.