Answer:
The author appeals to ethos:
B. By showing that the declaration's signers are serious because they pledge their lives to the contents of the document
Step-by-step explanation:
Ethos is an ethical appeal. When using this appeal, the writer evokes what the reader probably considers right and wrong. He suggests that he, the author, is also a well-behaved, ethical person, whose word can be trusted.
In the passage we are analyzing here, the author appeals to ethos by mentioning his and others' lives, fortunes, and honor. They are all pledging those very important things to the contents of the document. Clearly, the document possesses so much importance that it matches their own lives. This demonstrates how seriously they take the contents of the document and how they can be trusted from an ethical perspective.