Which of the Following Was One of the Justifications Given

Which of the following was one of the justifications given by William Seward for the purchase of Alaska?

A) The United States needed the land to conduct nuclear operations.
B) The fertile soil of Alaska would prove beneficial for America's agricultural industry.
C) The United States needed more land for expansion.
D) The long coastline of Alaska would improve trade relations with neighboring countries.
E) The United States needed a sea-link to Russia.