Answer:
C. Participle phrase
Explanation:
A Participle is a verb which acts as an adjective, describing a noun or pronoun. We have the present and past participles. In the phrase example given, 'curious' serves as the participle which describes the 'thing'.This tells us that the object in question is eager to learn about something.
So, the word curious, serves as both a description and the action word which is what a participle phrase means.
The correct answer is the first one
How to Write a Formal Letter?
Address or greet the concerned person properly like Dear Sir/Madam.
Always mention the subject of writing the letter.
Be concise in your letter. ...
The tone of the letter should be very polite and not harsh.
Write in a proper format and take care of the presentation of a letter.
Mention the address and date correctly.