Answer: 2) Bold but concerned.
Step-by-step explanation: The tone of a text or sentence is the author's or speaker's attitude towards the audience, the subject or even the characters of the text. There are many different kinds of tones, like: positive, negative, objective, sad, angry, etc. In the given excerpt from Abraham Lincoln's Letter to fellow Republican James T. Hale, we can see that his tone is bold (because he is proposing a prohibition against acquqiring territory), but it is also concerned about the decision he needs to make, and the situation the government is in.