A good starting point would be describing the Phoenicians. Saying who they were, when they rose and when they fell, etc. Then end the paragraph with "This is how this magnificent culture influenced Rome" then start your essay on how they influenced it with "The first way the Phoenicians influenced Rome is..."
The correct answer is C. Manifest destiny was the idea that the United States should stretch "from sea to shining sea". It was known as westward expansion.