From the given words, select the word which cannot be formed using the letters of the word HUMBLING, assuming that no letter is used more times than it appears in the original word.

Introduction / Context:
This question again checks letter-based reasoning using the base word HUMBLING. You must determine which of the options cannot be formed from its letters without adding any new letter or exceeding the available frequency. The task improves your ability to quickly verify whether a candidate word is compatible with a given pool of letters, an ability that is frequently tested in verbal reasoning sections.

Given Data / Assumptions:

• Base word: HUMBLING.
• Letters available: H, U, M, B, L, I, N, G (each exactly once).
• Options: BLUE, NUMB, LUNG, GLUM.
• No extra letters can be introduced and no letter can be used more than once.

Concept / Approach:
We list all distinct letters of HUMBLING and then examine each option word. If every letter in an option is present in the base word, with required frequency, then that word can be formed. If there is any letter in the option that does not appear in HUMBLING, that option is impossible to construct and will be our answer. Here, the most suspicious letter is E, which may or may not appear in the base word, so we pay special attention to it.

Step-by-Step Solution:
Step 1: Note letters in HUMBLING: H, U, M, B, L, I, N, G. Step 2: Check NUMB: N, U, M, B are all present in the base word, so NUMB can be formed. Step 3: Check LUNG: L, U, N, G are also present, so LUNG can be formed. Step 4: Check GLUM: G, L, U, M all occur in HUMBLING, so GLUM can be formed. Step 5: Check BLUE: B, L, U are present but the letter E does not appear anywhere in HUMBLING. Therefore BLUE cannot be formed from the base word.

Verification / Alternative check:
To verify quickly, form the letter set {H, U, M, B, L, I, N, G}. Compare this set with each option. NUMB, LUNG and GLUM use only letters from this set. However, BLUE contains the letter E, which is missing from HUMBLING. Since you are not allowed to introduce new letters, BLUE must be impossible. No frequency issues occur for the other options, so the check is complete and reliable.

Why Other Options Are Wrong:
NUMB, LUNG and GLUM all draw exclusively on letters that are present in HUMBLING. There is exactly one of each of these letters and none of these options demands any letter more than once, so they are valid constructions. Because the question is asking for the word that cannot be formed, these possible words are not correct answers.

Common Pitfalls:
Students sometimes misread HUMBLING as including the letter E or confuse I with E at a glance. Another pitfall is failing to list the base letters and instead relying on intuition, which increases the risk of overlooking a missing letter. To avoid these problems, always extract a clear set of base letters and deliberately check each option for extraneous letters. This habit will help not only in this question but in all similar letter-based reasoning problems.

Final Answer:
The only word that cannot be formed from HUMBLING is BLUE, so BLUE is the correct answer.