To answer this question, we need to understand the meaning of the given sentence and the context in which the word is used.
The sentence "If you need him, he can turn on a ____ and help you immediately" implies that someone can activate or utilize something to provide immediate assistance.
Let's go through each option to understand why it is correct or incorrect:
Option A) Penny - This option is incorrect because a penny is a small denomination of currency and cannot be used to provide immediate assistance.
Option B) Nickel - This option is incorrect because a nickel is also a small denomination of currency and cannot be used to provide immediate assistance.
Option C) Dime - This option is correct because a dime is a small denomination of currency and is commonly associated with the phrase "dime a dozen," which implies something that is easily available or readily accessible.
Option D) Quarter - This option is incorrect because a quarter is a larger denomination of currency and does not fit the context of providing immediate assistance.
The correct answer is C) Dime. This option is correct because a dime can be easily accessed and used to activate or utilize something for immediate assistance.