20.
Your Answer is
Correct Answer is J
Explanation
Item J: The content behind the underlined part explains the abstract noun beautiful subjects in front, so use a colon to connect, and J is correct.
Item F: The semicolon is used to separate two sentences, and the underlined part is not a complete sentence, F is wrong.
H item: Commas connect parallel words, the content behind the dash is not in parallel with the front, H is wrong.