The proper format is

No one really "said" it; it is the equation that represents Einstein's Theory of Relativity.
Answer:
C. This is not plagiarism
Explanation:
This would not be considered an example of plagiarism. In this example, the student takes some ideas from the original source of Reigeluth and Schwartz (1989). However, he mentions the source of such ideas in his text, while providing the relevant information that is needed for citations, such as author and date. He also rewrites the ideas he is borrowing in his own words.
Answer:
You should never include or integrate conclusion into the section for the results of your study
Explanation:
A research paper or an excerpt have different sections that make up the entire paper with each section having what it contributes to the essay or research or excerpt in general. You cannot write an introduction and a body of an essay or excerpt together; the same way that you cannot combine the result and conclusion section together. The result section is a standalone section that is usually followed by discussion and then conclusion. Hence integrating the conclusions into the result of this study is wrong.
Answer:
Labor Day pays tribute to the contributions and achievements of American workers
Explanation:
Labor Day pays tribute to the contributions and achievements of American workers and is traditionally observed on the first Monday in September. It was created by the labor movement in the late 19th century and became a federal holiday in 1894.