In the following sentence, one numbered part may contain a grammatical error, or the sentence may be fully correct. Choose the number of the part that has an error, or choose option (4) for No Error. Sentence: The vast majority of people are consuming (1) / suboptimal amounts of most micronutrients (2) / and most of the micronutrients concerning are very safe. (3)

Introduction / Context:
This question tests correct use of participle forms such as concerning and concerned, and it also encourages learners to read scientific sounding sentences without being distracted by technical vocabulary. The focus is on whether the final phrase micronutrients concerning is natural and grammatically correct in standard English when used in this particular position.

Given Data / Assumptions:

• The sentence is broken into three numbered parts, with option (4) representing No Error.
• The topic deals with micronutrient intake and safety.
• Part (1) uses the phrase are consuming, which is a present continuous form.
• Part (2) describes the amounts of micronutrients consumed.
• Part (3) contains the phrase most of the micronutrients concerning are very safe.

Concept / Approach:
The central concept here is adjective and participle usage after nouns. In standard English, when we want to say the micronutrients that are being discussed or the micronutrients in question, we usually use the adjective concerned, not concerning. The word concerning is more commonly used as a preposition meaning about, as in concerning this issue, or as a present participle verb form. The phrase micronutrients concerning, placed before the verb are, does not fit either usage well and sounds incorrect. Therefore, the correct expression should be most of the micronutrients concerned are very safe or most of the micronutrients in question are very safe.

Step-by-Step Solution:
Step 1: Examine part (1): The vast majority of people are consuming. This is a standard present continuous structure that fits the idea of ongoing dietary behaviour.Step 2: Examine part (2): suboptimal amounts of most micronutrients. This part is also correct and logically follows part (1).Step 3: Examine part (3): and most of the micronutrients concerning are very safe. Here, concerning is used directly after the noun micronutrients as if it were a post modifier, but it does not have the intended meaning.Step 4: Recognise that the writer wants to say most of the micronutrients under discussion are very safe, which is expressed by most of the micronutrients concerned.Step 5: Since the wrong participle form is used in part (3), this segment contains the grammatical error.Step 6: Conclude that the correct answer must be the number corresponding to this segment.

Verification / Alternative check:
To verify, replace concerning with concerned and read the full sentence: The vast majority of people are consuming suboptimal amounts of most micronutrients and most of the micronutrients concerned are very safe. This version is grammatically correct and clearly expresses the idea that the micronutrients being talked about are safe. Another alternative is most of the micronutrients in question are very safe, which again shows that the original word concerning was not appropriate in that position. No changes are required in the other two segments, confirming that only part (3) contains an error.

Why Other Options Are Wrong:
Option 1: Part (1) uses standard grammar, and the phrase are consuming is correctly formed.Option 2: Part (2) is grammatically fine and accurately describes suboptimal amounts of most micronutrients.Option 4: The sentence is not error free, because part (3) uses concerning incorrectly. Therefore, No Error cannot be chosen.

Common Pitfalls:
Learners sometimes accept incorrect usage because it sounds technical or academic, especially in scientific contexts involving words like micronutrients. Another pitfall is confusion between concerned and concerning. Remember that concerned after a noun generally means related to that noun, while concerning usually acts as a preposition meaning about. In grammatical error questions, exam setters frequently exploit such subtle distinctions, so careful reading and familiarity with standard collocations are important.

Final Answer:
The incorrect phrase appears in the third segment, so the correct option is 3.