Is - two billion dollars is a unit, one unit so it is singular and you use the singular verb
think - scientists is a plural, therefore, you must use the plural verb form of think
Answer:
It's Option D. Buck, Pearl S. <em>The Good Earth.</em> John Day, 1932.
Explanation:
Format for MLA citations: Last name, first name. <em>title</em>. publisher, date.
Now, look at your options and see which one follows this format. The only one option that follows MLA here is option D.
Buck, Pearl S. <em>The Good Earth.</em> John Day, 1932.
Answer:
Number 4 should be "should"
Number 5 should be "had better"
Other than that your answers are correct.
I believe the correct choice of answer would be A. Hope this helps!