Well you can certaily say that his assassination was the key reason which sparked the war, however, there were tensions going on before his assassination. On the Balkans there had been very strong desire for independence from the various nations which lived there, there was general unsatisfaction coming from Germany about its status with colonies, etc.
President pro tempore is someone who would preside in the absence of an officer. The true statement is "H.R. signifies a House bill and S signifies a Senate bill."
I think the correct answer from the choices listed above is option 4. A common goal of the Proclamation of Neutrality (1793), the Embargo Act (1807), and the Monroe Doctrine (1823) would be <span>encouraging independence movements in Latin America. Hope this answers the question.</span>