Which is an example of the concept of the manifest destiny in action

The concept of the 'manifest destiny' was basically the god given belief that the Americans, during the 19th century, obtained. This belief said that they were destined to expand and spread it's culture and government across the continent. The Americans used this to justify their expansion westward of America's borders in the 1800s.

However, I do not know the true answer relevant to the question unless you tell me and or list the answer choices. It seems as if this type of question would have them, hence the 'Which is an example'.

Your answer should be choice b!