Answer:
D. Farm equipment
Step-by-step explanation:
The U.S. exported farm equipment in the late 19th century because the country was already an industrialized nation.
The U.S. did not export Ivory because it comes from the tusks of elephants, and there are not elephants in the U.S. (only in zoos).
The U.S. did not export Bananas back then because they could not be grown in enough numbers.
And cuckoo clocks come from Germany.