Numbers 2, 3, and 5 should be the answers. Good luck!
The definition of diction is t<span>he choice and use of words and phrases in speech or writing. The most suited from the choices is therefore C), word choice.
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The sentence <em>Sickly people cost the company a whole boatload of dough </em>is not acceptable because the sentence contains a loaded word as well as slang.
You cannot use slang words such as <em>boatload </em>or <em>dough </em>in formal English.
It means, someone who adores plants and nature etc.