A sentence (or a part of the sentence) is underlined. Four alternatives are given to the underlined part which will improve the sentence. Choose the correct alternative. In case no improvement is needed, select "No improvement". Sentence: "The greater the demand, higher the price."

Introduction / Context:
This question tests your familiarity with a common comparative correlative structure in English: "The more X, the more Y" or "The greater the X, the higher the Y". The original sentence is almost correct but missing a key article in the second part. You must choose the option that completes this pattern properly and makes the sentence grammatically balanced and natural.

Given Data / Assumptions:

• Original sentence: "The greater the demand, higher the price."
• Underlined portion in effect is the second comparative phrase.
• Options: the high, a higher, the higher, No improvement.
• The sentence expresses an economic principle: as demand increases, price also rises.

Concept / Approach:
In English, when we use comparative correlatives such as "the more..., the more..." or "the greater..., the higher...", both parts need the article "the" before the comparative adjective. The correct pattern is "The greater the demand, the higher the price." Without "the" before "higher", the sentence sounds incomplete and breaks the parallel structure. Therefore, the best improvement is to insert "the higher" in the second clause.

Step-by-Step Solution:
Step 1: Identify the structure: "The greater the demand, ______ the price." The first part uses "The greater", signalling a comparative correlative structure. Step 2: Recall the standard pattern: "The + comparative, the + comparative." For example, "The sooner, the better" or "The more you study, the more you learn." Step 3: Examine option (a) "the high". This is not comparative; it uses the positive form "high" instead of "higher". Step 4: Examine option (b) "a higher". The article "a" breaks the parallelism and is not used in such correlative sentences. Step 5: Examine option (c) "the higher". This exactly matches the required comparative structure: "the higher the price". Step 6: Examine option (d) "No improvement". This would leave "higher the price" without "the", which is ungrammatical in this pattern. Step 7: Conclude that "the higher" is the correct improvement.

Verification / Alternative check:
Rewrite the sentence with the chosen option: "The greater the demand, the higher the price." This is a standard economic statement and reads naturally. Compare with similar expressions: "The stronger the wind, the colder it feels" or "The more you practise, the more confident you become." In each case, both comparatives are preceded by "the". The pattern is well established in English and supports the choice of "the higher".

Why Other Options Are Wrong:

• the high: Uses the positive adjective "high" instead of the comparative "higher", breaking the comparative relationship.
• a higher: The article "a" is not used in correlative comparatives; it would be "a higher price", but the sentence structure requires "the higher the price".
• No improvement: The original "higher the price" is missing the article "the" and does not fit the correlative pattern correctly.

Common Pitfalls:
Students sometimes treat comparative correlatives as two separate clauses and forget that both parts should mirror each other in form. As a result, they omit "the" before the second comparative. To avoid this, remember the fixed pattern: "The + comparative ..., the + comparative ...". Whenever you see a sentence beginning with "The more..." or "The greater...", check that the second part begins with "the" plus another comparative adjective or adverb.

Final Answer:
The correct improvement is "the higher", giving the full sentence: "The greater the demand, the higher the price."