In the following question, four words are given out of which one word is correctly spelt. Select the correctly spelt word related to the act of judging between opposing parties.

Introduction / Context:
This spelling question asks you to identify the correct form of a verb meaning "acts as an arbiter" or "settles a dispute between two parties". Such vocabulary appears in legal, business, and everyday contexts when someone is called upon to make a fair decision. Spelling this word correctly is important for formal writing and examinations.

Given Data / Assumptions:

We are looking for the correct spelling of the third-person singular form of the verb "arbitrate".
The correct base verb is arbitrate, meaning to act as a judge in a dispute.
The correct third-person singular present form should be "arbitrates".
The options include several variants with extra or misplaced letters.

Concept / Approach:
The root word is "arbitrate": a-r-b-i-t-r-a-t-e. To form the third-person singular present tense, we simply add "s" to get "arbitrates". No letters are doubled and the internal vowel sequence remains "arbi". Any spelling that alters this pattern or doubles the "t" unnecessarily is incorrect. Recognising the root and standard -s ending helps select the correct form easily.

Step-by-Step Solution:
Step 1: Recall the base verb "arbitrate" meaning to act as judge, especially to settle disputes. Step 2: Form the third-person singular present: arbitrate → arbitrates. Step 3: Examine option B "arbitrates" and verify that it preserves the root spelling and simply adds "s". Step 4: Option A "arbittrates" doubles the "t", which is not part of the standard spelling. Step 5: Option C "arbetrates" replaces the "i" with "e", breaking the root pattern "arbi". Step 6: Option D "arbettrates" both changes the vowel and doubles the "t", making it doubly incorrect. Step 7: Option E "arbitrattes" adds an extra "t" near the end, again deviating from "arbitrate".

Verification / Alternative check:
Check usage in an example sentence: "The judge often arbitrates disputes between neighbours." This spelling looks and sounds correct. If we tried "arbittrates" or "arbetrates", the words would look awkward and unfamiliar, and you would not find them in standard dictionaries. Recognising that many English verbs simply take an "s" in the third-person singular present without internal changes reinforces that "arbitrates" is the correct form.

Why Other Options Are Wrong:
Option A arbittrates erroneously doubles the "t", which is not required in this verb form.
Option C arbetrates uses "e" instead of "i", changing the pronunciation and breaking the root "arbit-".
Option D arbettrates combines both the wrong vowel and an unnecessary double "t".
Option E arbitrattes introduces an extra "t" and deviates from the standard "arbitrate + s" pattern.

Common Pitfalls:
Students sometimes overthink spellings and introduce double consonants where they are not needed, especially in multi-syllable words. A reliable method is to locate the root word in your memory (arbitrate) and simply attach standard tense or person endings to it. If the root does not change, the derived forms should keep the same internal sequence of letters, avoiding random doubling or vowel changes.

Final Answer:
The correctly spelt word is "arbitrates".