In the following question, choose the word that is most similar in meaning to “Inhibitor” as used in general English and science.

Introduction / Context:
The word “inhibitor” is widely used in science and general English to describe something that slows down, prevents or restrains a process, reaction or behaviour. In biology and chemistry, an inhibitor blocks or reduces the activity of another substance. In everyday language, any factor that holds back progress can also be called an inhibitor. The synonym must reflect this idea of obstruction or restraint.

Given Data / Assumptions:
- Target word: Inhibitor.
- Options: Advocate, Subsidy, Avoidance, Compensation, Hindrance.
- We assume the generic meaning: something that inhibits or restrains an action, reaction or development.

Concept / Approach:
The root verb of “inhibitor” is “inhibit”, which means to slow down, restrict or prevent. Therefore, we look for a noun that conveys obstruction or obstacle. “Hindrance” is a direct match. The other options refer to support, payment or a type of behaviour and do not express the idea of blocking or restraining something.

Step-by-Step Solution:
Step 1: Recall the meaning of “inhibit”: to slow, prevent or discourage an action. Step 2: Transform that into a noun: an “inhibitor” is anything that performs this restraining function, like a chemical that slows a reaction or a rule that stops a behaviour. Step 3: Check option E: “Hindrance”. This word means an obstacle or something that makes progress slow or difficult. Step 4: Compare with option A: “Advocate”, which is someone who supports or argues in favour of something, not someone who blocks it. Step 5: Option B: “Subsidy” is a financial aid that encourages an activity, again the opposite of an inhibitor. Step 6: Option C: “Avoidance” means the act of keeping away from something; it is a behaviour, not a blocking factor itself. Step 7: Option D: “Compensation” refers to payment for loss or damage, unrelated to the act of inhibiting. Step 8: Therefore, “Hindrance” is the only option that correctly expresses the meaning of “inhibitor”.

Verification / Alternative check:
Use the words in parallel sentences: “Lack of funding is a serious inhibitor of scientific progress” can be rephrased as “Lack of funding is a serious hindrance to scientific progress.” The meaning remains almost identical. However, replacing “inhibitor” with “subsidy” or “advocate” would reverse the sense, showing that those options are not synonyms.

Why Other Options Are Wrong:
- Advocate: actively supports; it facilitates rather than blocks action.
- Subsidy: a financial support that promotes activity; it is like the opposite of an inhibitor.
- Avoidance: refers to a pattern of behaviour, not a factor that blocks an external process.
- Compensation: payment made for loss; does not involve preventing or slowing anything.

Common Pitfalls:
Some candidates may select “avoidance” because they associate both words with stopping something. However, “avoidance” is what a person might do; an “inhibitor” is the thing that prevents or slows the person or process. It is important to distinguish between behaviour words and words that name an external restraining factor. Focusing on the core idea “obstacle, restraining factor” points clearly to “hindrance”.

Final Answer:
The word most similar in meaning to “Inhibitor” is Hindrance.