A counterargument should appear shortly before the conclusion of an argument essay.
In order to show that you've done well rounded research, you should always add a counterargument and refute that in your essay. This means you bring up an opposing point, and then give more detail on how your position overcomes that opposition. It should appear after you've given the reader the bulk of your research (but before your conclusion).
Pluto is considered a dwarf planet
B) a sonnet is a rhyming poem of fourteen lines.
If the whole first sentence was bolded then it's an independent clause because it can be by itself. However, none of it's bolded.