Question

a petition to the president of the united states july 17, 1945
the following selection is a petition, in the form of a letter, written to president truman and signed by 70 eminent scientists in 1945.
1 discoveries of which the people of the united states are not aware may affect the welfare of this nation in the near future. the liberation of atomic power which has been achieved places atomic bombs in the hands of the army. it places in your hands, as commander - in - chief, the fateful decision whether or not to sanction the use of such bombs in the present phase of the war against japan
2 we, the undersigned scientists, have been working in the field of atomic power. until recently we have had to fear that the united states might be attacked by atomic bombs during this war and that her only defense might lie in a counterattack by the same means. today, with the defeat of germany, this danger is averted and we feel impelled to say what follows:
3 the war has to be brought speedily to a successful conclusion and attacks by atomic bombs may very well be an effective method of warfare. we feel, however, that such attacks on japan could not be justified, at least not unless the terms which will be imposed after the war on japan were

1. what is the most likely reason the author included paragraphs 1 and 2?

options:
to provide background and purpose for the letter and to establish the credibility of the author(s)
to state that the united states government has been keeping a secret from the american people
to establish the president of the united states as the commander - in - chief and to state that the united states government has been keeping a secret from the american people
to provide background and purpose for the letter and to make the point that the united states government has been keeping a secret from the american people

Explanation:

Paragraphs 1 and 2 introduce the scientists' work in atomic power and the fear of atomic attack, aiming to give context (background) and show they have expertise (credibility) to support their petition's purpose. The first option matches this: providing background and purpose, and establishing credibility. Other options focus on secrets or establishing the President/Commander - in - Chief, which isn't the main intent.

Answer:

To provide background and purpose for the letter and to establish the credibility of the author(s)