Respuesta :
Answer: c
Explanation:
It provides an illustration of how the US Navy threatened to use force to open Japanese ports.
The way the letter supports MacGregor's point is that C. It provides an illustration of how the US Navy threatened to use force to open Japanese ports.
What is a Supporting Detail?
This refers to the use of evidence to show the validity of a claim either with the use of factual or statistical data.
Hence, we can see that from the given text, we can see that there is the narration of the way the US Navy forced the Japanese to open their ports and this was a supporting detail for MacGregor.
Read more about supporting details here:
https://brainly.com/question/884525
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