In the following passage, some words have been left out. Read the passage carefully and select the correct answer for the blank. The promise of nuclear power has so _____ outweighed all of these concerns, and India has reason to be proud of its technology and determination to look for non fossil options in its energy planning.

Introduction / Context:
This question is from a cloze passage about energy policy and the role of nuclear power. The sentence talks about how strongly the advantages or promise of nuclear power have outweighed concerns. The blank requires an adverb that forms a natural collocation with so and the verb outweighed. A strong grasp of common English phrases and collocations is essential to solve this kind of question accurately.

Given Data / Assumptions:

• Sentence fragment: The promise of nuclear power has so _____ outweighed all of these concerns.
• The clause continues with: and India has reason to be proud of its technology and determination to look for non fossil options in its energy planning.
• Options: far, less, near, closely.
• The overall meaning is that advantages are much greater than concerns.

Concept / Approach:
In English, the phrase so far outweighed is a standard idiomatic combination. It means that one thing is much more important or much heavier in importance than another. The adverb far is used to intensify comparisons, especially with comparative adjectives or participles like outweighed. The other adverbs in the options do not collocate naturally here or would change the sense of the sentence. Therefore, recognising common patterns like so far outweighed is the key to choosing the correct option.

Step-by-Step Solution:
Step 1: Identify the comparison being made. The sentence compares the promise of nuclear power to concerns about it.Step 2: Understand that outweighed already means was more important or heavier in importance than.Step 3: Note that the word so before the blank suggests an intensifying adverb is required, such as far, greatly or much.Step 4: Test the option far: The promise of nuclear power has so far outweighed all of these concerns. This sounds natural and strongly emphasises the imbalance.Step 5: Try other options: so less outweighed, so near outweighed, so closely outweighed; all of them sound unnatural or incorrect.Step 6: Conclude that far is the only choice that forms a correct and idiomatic phrase.

Verification / Alternative check:
You can check the phrase by comparing with similar sentences. For example, The benefits have so far outweighed the costs is a common structure meaning that until now the benefits are much greater. Here, the passage uses a very similar idea: the promise of nuclear power has so far outweighed concerns. The grammar, sense and collocation are all correct when far is inserted. None of the other options produce a phrase that a native speaker would normally use in serious writing about policy or technology.

Why Other Options Are Wrong:
Less: The combination so less outweighed is not a standard construction. Less is not used in this way before a past participle to intensify a comparison. It would also weaken the meaning instead of emphasising it. Near: Near refers to physical or metaphorical closeness in distance or time. It does not express degree in comparisons with outweighed. Closely: Closely suggests small difference or similarity, as in closely matched, which contradicts the idea that the promise is much stronger than the concerns. It would suggest the concerns are almost equal, not much weaker.

Common Pitfalls:
Students sometimes ignore collocations and focus only on what seems grammatically possible. While less or closely might look like adverbs that could fit a blank, they do not form a real idiomatic phrase with outweighed. Another common mistake is to think of so far only in the temporal sense of until now and become confused. In this sentence, far functions as an intensifier in a comparison, which is also a well established use. To handle cloze passages effectively, pay close attention to pairs of words that often appear together and rely on your familiarity with natural English phrasing.

Final Answer:
The adverb that correctly completes the sentence is far, giving the phrase has so far outweighed all of these concerns.