In the question below, four words are given in bold, which may not be arranged in the correct order. Choose the pair of words that need to be interchanged to make the sentence grammatically correct and meaningful.

A/an privacy (A) drawback (B) of modern social platforms is that users can publish statements in complete significant (C) without facing immediate accountability (D).

The correct option is Only (A)-(C).

Step-by-step Explanation:

Let's analyze the context and grammatical role of each bold word in the original sentence:
Original Sentence: "A/an privacy (A) drawback (B) of modern social platforms is that users can publish statements in complete significant (C) without facing immediate accountability (D)."

1. Position (A): The word precedes the noun "drawback", so an adjective is needed to describe the noun. "Privacy" is a noun, whereas "significant" is an adjective. Replacing "privacy" with "significant" forms the grammatically sound noun phrase "A significant drawback".
2. Position (C): The modifier "complete" requires a noun following it to complete the phrase "in complete [noun]". "Significant" is an adjective, whereas "privacy" is a noun. Placing "privacy" here yields the meaningful phrase "in complete privacy".

By swapping (A) privacy and (C) significant, the corrected sentence becomes:
"A significant (A) drawback (B) of modern social platforms is that users can publish statements in complete privacy (C) without facing immediate accountability (D)."

Hence, the pair of words that must be interchanged is (A)-(C).