Choose the most appropriate word to complete the sentence: “The president and his coterie of advisers were unable to offer him a ____________ to the national problem.”

Introduction / Context:
Here the sentence describes a political leader and his group of advisers facing a serious national problem. The blank must be filled with a noun that names what the advisers could not provide. In ordinary English, when we talk about a problem of any kind, we naturally talk about finding a “solution” or a “remedy”. Because this is a formal sentence about a national problem, the most straightforward and common word is “solution”.

Given Data / Assumptions:
- Sentence: “The president and his coterie of advisers were unable to offer him a ____________ to the national problem.”
- Options: solvent, solute, solution, mixture, remedy.
- Context: politics, decision making, problem solving at national level.

Concept / Approach:
The scientific words “solvent”, “solute” and “solution” are often confused, but only “solution” is also commonly used metaphorically for answers to problems. “Remedy” can also be used, but the verb “offer” plus the preposition “to” is much more natural with “solution to a problem”. Thus, we look for the most idiomatic combination with “to the national problem”.

Step-by-Step Solution:
Step 1: Insert “solution”: “unable to offer him a solution to the national problem.” This is a very common English phrase describing failure to solve a problem. Step 2: Consider “solvent”. A solvent is a liquid that dissolves another substance, used in chemistry. It is not used to refer to answers to political or social problems. Step 3: Consider “solute”. This refers to the substance that is dissolved in a solvent, again purely scientific. Step 4: Consider “mixture”. A mixture is a combination of substances; saying “a mixture to the national problem” is nonsensical. Step 5: Consider “remedy”. While “remedy for a problem” is possible, the pattern “offer a remedy to the national problem” is less common than “offer a solution to the national problem”. Step 6: Therefore “solution” is the best and most idiomatic answer.

Verification / Alternative check:
In standard English usage, we routinely read phrases like “seek a solution to the crisis” or “find a solution to the problem”. Such collocations are frequent in news reports and formal essays. In contrast, phrases with “remedy to the problem” are rarer and sound slightly less natural in this context. Thus, the exam setter clearly expects “solution”.

Why Other Options Are Wrong:
- Solvent: scientific term; does not carry the meaning of an answer or resolution here.
- Solute: limited to physical chemistry, not problem solving.
- Mixture: describes a combination of substances, not a political answer.
- Remedy: although related to cures, it is less idiomatic than “solution” with the preposition “to” in this specific sentence.

Common Pitfalls:
The main trap is confusion due to similar spelling between “solution”, “solvent” and “solute”. Remember that “solution” is the only one widely used for both chemical mixtures and figurative answers to problems. Solvent and solute remain technical terms without that metaphorical extension in everyday language. Keeping this distinction clear helps avoid mistakes in vocabulary questions.

Final Answer:
The word that best completes the sentence is solution.