Question

Pick the most appropriate auxiliary verb to fill in the blank:
CCTV _______ been used for many years for the surveillance of public areas associated with obvious risk. 

• A. is
• B. are
• C. has
• D. have

Answer 1

The Correct Option is C

To solve this question, we need to determine which auxiliary verb best fits in the given sentence:

"CCTV _______ been used for many years for the surveillance of public areas associated with obvious risk."

The options provided are:

1. is
2. are
3. has
4. have

First, let's analyze the structure of the sentence. The phrase "been used" suggests the present perfect tense, which is formed using the auxiliary verbs "has" or "have" followed by the past participle of the main verb.

Next, we look at the subject of the sentence, which is "CCTV". The term "CCTV" stands for "Closed-Circuit Television," which is a singular noun. In English grammar, we use "has" with singular subjects and "have" with plural subjects.

Therefore, the correct auxiliary verb to use in this context is "has" because "CCTV" is singular.

Here's the correctly completed sentence:

"CCTV has been used for many years for the surveillance of public areas associated with obvious risk."

Let's briefly rule out the other options:

• is: Incorrect because "is" is used in continuous tenses, not perfect tenses.
• are: Incorrect because "are" is used with plural subjects or for forming the present continuous tense.
• have: Incorrect because "have" is used with plural subjects, and "CCTV" is singular.

Therefore, the correct answer is "has".