Read this excerpt from Susan Butcher and the Iditarod Trail.

Then the two sick children died in Nome and more were ill. The governor made his decision; it would be sled-dog teams on the land route.

What can a reader infer based on the information in the excerpt?

Pressure from the US government pushed the governor to make a decision.
Pressure from doctors all over Alaska pushed the governor to make a decision.
The increasing number of sick people in Nome pushed the governor to make a decision.
The increasing number of sled-dog teams pushed the governor to make a decision.