Correct Answer: C

Rationale: In this sentence, 'It's' is the contraction for 'it is,' and 'than' is used correctly for comparisons (e.g., better than). Therefore, sentence C is correct because it uses 'It's' (it is) and 'than' (for comparison) properly. Choices A, B, and D are incorrect. Choice A lacks the necessary apostrophe in 'It's' (it is) and incorrectly uses 'then' instead of 'than.' Choice B incorrectly uses 'Its' (possessive form) instead of 'It's.' Choice D lacks the necessary apostrophe in 'It's' (it is) and incorrectly uses 'then' instead of 'than.'

Correct Answer: D

Rationale: The correct answer is 'Mid-America.' It is correctly hyphenated as it combines 'Mid' and 'America' to form a compound noun. Choice A, 'Ex-president,' should be hyphenated to show the prefix 'Ex-' before 'president.' Choice B, 'Hyperactive,' should not be hyphenated as 'hyper' is a prefix. Choice C, 'Self-made,' should be hyphenated to connect 'self' and 'made' in this compound adjective.

Correct Answer: D

Rationale: The correct answer is D, 'Exclamation mark.' Exclamation marks are used to express strong emotions such as excitement, surprise, or urgency. They indicate a heightened level of emotion in a sentence. Periods (A) are used to indicate the end of a statement, commas (B) are used to separate elements in a sentence, and question marks (C) are used to indicate questions or uncertainty. In this context, the use of an exclamation mark is the most appropriate choice to convey a strong feeling or emotion.

Correct Answer: A

Rationale: The correct use of quotation marks in choice A is to enclose the title of a book, 'Where the Red Fern Grows,' indicating that it is a specific title that should be distinguished from the rest of the sentence. Choice B incorrectly uses quotation marks for movie titles, which should be italicized or underlined. Choice C correctly uses quotation marks for the title of a poem. Choice D has an extra space before the opening quotation mark, which is incorrect.

Correct Answer: A

Rationale: In the sentence provided, the words that function as nouns are 'Robert,' 'sources,' 'project,' 'databases,' and 'research.' These words are all objects or concepts that can be referenced or identified in a sentence as nouns. Choice B includes adjectives ('final,' 'academic') which describe other nouns rather than being nouns themselves. Choice C includes a pronoun ('he') which is not a noun. Choice D lacks the noun 'Robert' which is a subject in the sentence.