Final answer:
The concept of Manifest Destiny embraced the idea of US westward expansion and the Americanization of residents in the acquired territories, while also linking expansion with the spread of freedom.
Step-by-step explanation:
The concept of Manifest Destiny embraced the idea that the United States would expand "from sea to shining sea," and that the residents of areas under expansion would be Americanized. Additionally, it promoted the belief that spreading the boundaries of the United States was equivalent to spreading freedom.
With this in mind, out of the options given, the one that best exemplifies the concept of Manifest Destiny is a. westward expansion in the US. Westward expansion in the United States involved the acquisition of territory and the Americanization of the people living in those areas, aligning with the principles of Manifest Destiny.