English Vocabulary — Choose the closest meaning (contextual synonym). Sentence: In spite of their efforts, the team of scientists could not make much headway to solve the problem.

Introduction / Context:
This question tests your ability to recognize contextual synonyms used in formal writing. The phrase “make much headway” frequently appears in research reports, news articles, and project updates to describe the amount of progress achieved. Understanding this idiom helps you read academic and professional texts with accuracy.

Given Data / Assumptions:

• The clause is: “could not make much headway.”
• Domain context: scientific team working to solve a problem.
• Options relate to nouns that could replace “headway.”
• We must choose the word closest in meaning while preserving the sentence logic.

Concept / Approach:
“Headway” in modern English means “forward movement or progress toward a goal.” In research contexts, it specifically means measurable advancement. Therefore, the best single-word replacement is “progress.” Alternatives like “start” or “thinking” do not convey advancement toward a target; “efforts” describes input rather than outcome.

Step-by-Step Solution:

Verification / Alternative check:
Replace directly: “In spite of their efforts, the team of scientists could not make much progress to solve the problem.” This keeps the semantics identical and is idiomatic in formal English. Many style guides explicitly list “headway = progress.”

Why Other Options Are Wrong:

• thinking: Refers to mental activity, not advancement.
• efforts: Describes attempts/input, not results/outcome.
• start: Means beginning; not ongoing advancement.

Common Pitfalls:
Learners sometimes confuse input (“effort”) with output (“progress”). Also, they may guess “start” because headway sounds like “heading off,” but context demands outcome, not initiation.

Final Answer:
progress