Answer:
D. The speaker believes the greatness of Britain could disappear, just as did that of Nineveh and Tyre.
Step-by-step explanation:
The speaker in Recessional by Rudyard Kipling shouts to God, the Lord of their fight line under whose hand they hold control over the land. He requires the "Ruler God of Hosts" to be with them in case they overlook.
Their naval forces return home, the flame of war goes out, and all the pageantry and radiance of yore is "one with Nineveh and Tire". The speaker calls for God, the "Judge of Nations", to save them "lest they forget".