Which lines from this excerpt of Jefferson Davis’s Inaugural Address show that Davis believed that he and his fellow citizens had the right to rebel against the government if it failed them?

A. Called to the difficult and responsible station of Chief Executive of the Provisional Government which you have instituted, I approach the discharge of the duties assigned to me with an humble distrust of my abilities, but with a sustaining confidence in the wisdom of those who are to guide and to aid me in the administration of public affairs, and an abiding faith in the virtue and patriotism of the people.
B … I enter upon the duties of the office to which I have been chosen with the hope that the beginning of our career as a Confederacy may not be obstructed by hostile opposition to our enjoyment of the separate existence and independence which we have asserted, and, with the blessing of Providence, intend to maintain.
C.Our present condition, achieved in a manner unprecedented in the history of nations, illustrates the American idea that governments rest upon the consent of the governed, and that it is the right of the people to alter or abolish governments whenever they become destructive of the ends for which they were established.
D. The declared purpose of the compact of Union from which we have withdrawn was "to establish justice, insure domestic tranquillity, provide for the common defense, promote the general welfare, and secure the blessing of liberty to ourselves and our posterity;" and when, in the judgment of the sovereign States now composing this Confederacy, it had been ed from the purposes for which it was ordained, and had ceased to answer the ends for which it was established, a peaceful appeal to the ballot-box declared that so far as they were concerned, the government created by that compact should cease to exist. In this they merely asserted a right which the Declaration of Independence of 1776 had defined to be inalienable ...
I think the answer is C

I agree.

Yes, you are correct. The line that shows that Davis believed in the right to rebel against the government if it failed them is C. It states: "Our present condition, achieved in a manner unprecedented in the history of nations, illustrates the American idea that governments rest upon the consent of the governed, and that it is the right of the people to alter or abolish governments whenever they become destructive of the ends for which they were established." This line suggests that Davis believed in the people's right to change or overthrow a government that no longer served their interests or purposes.

You are correct, the line "Our present condition, achieved in a manner unprecedented in the history of nations, illustrates the American idea that governments rest upon the consent of the governed, and that it is the right of the people to alter or abolish governments whenever they become destructive of the ends for which they were established" from Jefferson Davis's Inaugural Address shows that Davis believed that he and his fellow citizens had the right to rebel against the government if it failed them.