I believe it would be A. and C.
Hope it helps.
Answer: A. Navajo Indians in the U.S. Marine Corps developed an unbreakable code using their native language.
Navajo is a language that is not written and is very complex with its incomprehensible syntax, tonal qualities and especially the dialects. That is the main reason that Navajo language was used to secure communications during the war.
An indentured servant was someone who would pay for his journey to the US or for his debt by serving the person who helped him and after a while the debt would be over and the person would be free. The person would have all rights like regular people. Slaves had no rights at all and were not even observed as people and their slavery would never end unless the owner specifically freed them. Slavery was not contractual unlike indentured serviture.
The correct answer is "Elected leaders were capable of abusing their power."
For Lyndon B. Johnson, he abused the powers given to him in the Gulf of Tonkin Resolution passed by the United States Congress. His massive escalation in Vietnam despite the lack of US success shows how he abused his executive power.
For Richard Nixon, he tried to cover up a huge break in to the Democratic National Convention headquarters at the Watergate complex. He tried to use the excuse of "executive privilege" as a means to keep his recorded conversations from the American public.
Explanation:
The main concern with John Dickerson's first draft of the articles of confederation is that it made the federal/central government weak and incapable of enforcing significant laws; this was possible because the first draft put too much authority and power in the hands of state governments.