In the following question, the sentence is given with a blank to be filled in with an appropriate word. Select the correct alternative out of the four and indicate it by choosing the appropriate option.\n\n"The fun ____________ reduced significantly when mom decided to tag along."

Introduction / Context:
This vocabulary and usage question tests your familiarity with common modern expressions, particularly the phrase fun quotient. The sentence talks about how the level of fun changed when a parent decided to join an activity. You must choose the noun that best completes the sentence in a natural and idiomatic way. Questions like this assess whether you can recognise the correct collocation used in contemporary English.

Given Data / Assumptions:

• Sentence: The fun ____________ reduced significantly when mom decided to tag along.
• Options: mark, sign, quotient, moment.
• The intended meaning is that the overall level or amount of fun became lower when the mother joined.
• We assume that the tone is informal and conversational.

Concept / Approach:
The phrase fun quotient is a popular and widely used informal expression. Quotient normally means the result of division in mathematics, but in everyday language it is extended metaphorically to mean level, proportion, or degree, as in entertainment quotient or style quotient. Thus, fun quotient refers to how much fun there is in a situation. None of the other options form a known and natural collocation with fun in this context.

Step-by-Step Solution:
Step 1: Consider the meaning of the sentence: the presence of mom lowered the level of fun. Step 2: Test each option in the blank and see which one produces a natural phrase. Step 3: The fun mark reduced sounds awkward and is not a standard expression. Step 4: The fun sign reduced also sounds unnatural because sign does not usually collocate with fun in this way. Step 5: The fun moment reduced is incorrect because moment usually refers to a particular point in time, not to the overall level of fun. Step 6: The fun quotient reduced significantly is idiomatic and clearly communicates that the amount of fun decreased.

Verification / Alternative check:
You can check this by comparing with other similar phrases: style quotient, glamour quotient, and entertainment quotient are all common in modern English. Replacing fun with these words still produces clear expressions that describe levels of style, glamour, or entertainment. No such pattern exists with mark, sign, or moment in a similar way. This confirms that quotient is the only choice that fits the pattern used in actual language.

Why Other Options Are Wrong:
Option A, mark, typically appears in phrases like watermark, hallmark, or mark of respect. The combination fun mark is not standard. Option B, sign, is used in expressions like sign of trouble or sign of respect, but not in fun sign with this meaning. Option D, moment, is used in phrases such as moment of joy, but then it would be a fun moment rather than fun moment reduced, and that would describe a specific point in time, not the overall level of fun across the event.

Common Pitfalls:
Students who are not familiar with the metaphorical use of quotient might hesitate to choose it because they only associate it with mathematics. Others might choose mark because they have seen phrases like benchmark or mark of quality and think that anything with mark must relate to measurement. However, in this exact context, quotient is the phrase that aligns with contemporary usage patterns in informal English.

Final Answer:
The correct word is quotient, so the sentence should read: The fun quotient reduced significantly when mom decided to tag along.