From the given alternative words, select the word which cannot be formed using the letters of the word EXORBITANT.

Introduction / Context:
This question belongs to the word formation category where one must decide which of the given options cannot be formed from the letters of the base word. The base word here is EXORBITANT. The key is to consider the frequency of each letter in the base word and ensure that any constructed word does not demand more instances of a letter than are available.

Given Data / Assumptions:

• The base word is EXORBITANT.
• We can use each letter only as many times as it appears in EXORBITANT.
• Available letters and counts are: E(1), X(1), O(1), R(1), B(1), I(1), T(2), A(1), N(1).
• The option words are BITTER, EXPORT, EXNORA, and EXTANT.

Concept / Approach:
We check each option word letter by letter. For every letter, we compare how many times it appears in the option with its count in EXORBITANT. If an option requires more copies of any letter than are present in EXORBITANT, that option cannot be formed. If all letters are within the available counts, the word can be formed.

Step-by-Step Solution:
Step 1: Consider BITTER. Letters are B, I, T, T, E, R. EXORBITANT contains B(1), I(1), T(2), E(1), and R(1), so BITTER can be formed exactly using these letters. Step 2: Consider EXTANT. Letters are E, X, T, A, N, T. EXORBITANT contains E(1), X(1), T(2), A(1), and N(1). All required letters and counts are available, so EXTANT can also be formed. Step 3: Consider EXNORA. Letters are E, X, N, O, R, A. The base word has exactly one of each of these letters, so EXNORA can be formed. Step 4: Consider EXPORT. Letters are E, X, P, O, R, T. We must check if P is present in EXORBITANT. Step 5: The letters in EXORBITANT do not include P at all. Therefore, EXPORT cannot be formed from EXORBITANT because it requires the letter P which is not available.

Verification / Alternative check:
To verify, we can again list the unique letters in EXORBITANT and confirm that P is missing. All the other letters in EXPORT (E, X, O, R, T) are present, but the absence of P alone is enough to make the formation impossible. The other options use only letters that exist in EXORBITANT within allowed counts.

Why Other Options Are Wrong:
BITTER uses two T letters, one B, one I, one E, and one R, all of which are available in adequate numbers. EXNORA uses one each of E, X, N, O, R, and A, all present. EXTANT uses two Ts and one each of E, X, A, and N, which are also available. Hence, these options can be formed and are not correct answers to the question of impossibility.

Common Pitfalls:
A frequent error is to check only whether all letters appear at least once, without considering the count of repeated letters such as T in BITTER and EXTANT. Here that is not problematic, but in other similar questions it may be crucial. Another mistake is overlooking a letter like P and assuming that EXPORT is fine because it looks similar to part of EXORBITANT.

Final Answer:
The word that cannot be formed from the letters of EXORBITANT is EXPORT.