Answer:
A) Settlers rushed to California to find gold.
Explanation:
In the informational text "The Pony Express", the history of the Pony Express is given. The text follows the events that led to the introduction of the Express and then the eventual developments in relaying long-distance messages.
Among the given events, the first thing that happened was the finding of gold in California and the settlers rushing to that place. This was in 1848, after which came to the start of the Pony Express in 1860. This was followed by the completion of the first telegraph line in 1961 and then, in 1869, the train line to California was finished.
Thus, the correct answer is option A.
