Which detail in "Trail Mail!" shows why a speedy mail service was so
important to the nation?
A) Each Pony Express rider traveled
for an average of six hours.
B) William Russell and his partners
built two hundred relay stations
along the 1,966-mile route.
C) Families received bad news too
late to help, and good news too
late to join the celebration.
D) Senator William M. Gwin lobbied
Congress to approve a shorter
mail route

The Pony Express helped mails to deliver faster from one place to another in a short period.

Explanation:

Sending mails from one place to another was difficult, which took more than a week to send it to its destination. Letters sent through ships which regularly operated because of the supply of the goods. Homing pigeons, stagecoach, and railroads were some other methods to sent mails. To reduce the time a speedy mail service was introduced, which came to be known as the Pony Express. The Pony express sent letters from one place to another in a short time through a system of many riders that would gallop (ride horses) across the land to deliver mail. The fast mails help people living far from cities to be connected with recent activity and supported the military to maintain law and order in their stations.

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