I think the answer is a. The Senate. I hope this helps!!!! :)
Compared with earlier presidents, modern presidents are moved involved in the legislative process, since the role of early Presidents was largely confined to foreign policy, whereas more modern presidents will play a more active role in pushing for certain legislation.
The immediate cause of World War I that made the aforementioned items come into play (alliances, imperialism, militarism, nationalism) was the assassination of Archduke Franz Ferdinand of Austria-Hungary. (Hope I helped:))
The correct option is D. During the last six months of the war, the United States of America, release atomic bombs on two different cities of Japan within a short space of interval. This move was not expected at all by the Japanese and it served as the final stroke that breaks the elephant's back. It leads to quick surrender by the Japanese.