In the following question on spelling, four words are given. Out of these, select the word that is incorrectly spelt.

Introduction / Context:
This spelling based question presents four words that look similar to their correct forms. Three are correctly spelt, while one contains a subtle but important error. Such questions are common in competitive exams to test attention to detail and familiarity with standard written English. The words here are of moderate difficulty and often appear in essays, reports, and formal letters, making them useful for real life writing as well.

Given Data / Assumptions:

• Options: Tranquillity, Perseverence, Resplendence, Accommodation.
• The task is to identify the incorrectly spelt word.
• We assume standard British or widely accepted spellings.
• Each word is a common noun used in formal contexts.

Concept / Approach:
The key is to know or recall the correct spellings. Tranquillity is correctly spelt with a double l in standard British English. Resplendence, meaning brilliant or glowing quality, is correctly formed. Accommodation is correctly spelt with double c and double m. The problematic option is Perseverence, where the last part should be ance instead of ence. The correct spelling is Perseverance, meaning continued effort in spite of difficulty. Recognising the common suffix patterns ance versus ence is helpful here.

Step-by-Step Solution:
Step 1: Examine Tranquillity. In British English, tranquillity is spelt t r a n q u i l l i t y, with double l. The given spelling matches this. Step 2: Examine Accommodation, which is correctly spelt a c c o m m o d a t i o n, with both double c and double m. The option shows these doubles correctly. Step 3: Examine Resplendence, spelt r e s p l e n d e n c e, which is a standard spelling for the noun meaning brilliance. The given spelling is correct. Step 4: Examine Perseverence. The correct word is Perseverance, with the ending a n c e, not e n c e. The option mixes up these vowels. Step 5: Recognise that Perseverence is therefore an incorrect spelling intended as the answer. Step 6: Conclude that among the four, Perseverence is the word that is not spelt according to standard usage.

Verification / Alternative check:
Looking at real usage, one finds perseverance in motivational writing and exam passages, always ending with a n c e. Tranquillity, Resplendence, and Accommodation are also widely used in correct forms in textbooks and articles. If we try to search for Perseverence in authoritative dictionaries, it will not appear as a headword; instead, they will redirect to Perseverance. This confirms the error. Noticing typical suffix spellings like performance, endurance, perseverance (with ance) and difference, excellence (with ence) is a useful technique.

Why Other Options Are Wrong:
Tranquillity is correct in British English, and even in other variants it appears with either one or two l letters; exam boards usually accept the British double l spelling. Resplendence is correctly spelt and appears as such in literature describing glowing or magnificent beauty. Accommodation is a classic example of a word with double c and double m, and the provided spelling matches this pattern exactly. Therefore, none of these can be the incorrect spelling.

Common Pitfalls:
A common error is to doubt long words like Accommodation or Tranquillity, which learners know are tricky, and to overlook the less obvious change from ance to ence in Perseverence. Students often confuse these two suffixes because they sound similar. A good habit is to learn difficult words along with their word families; for example, persevere leads naturally to perseverance with ance. Visual memory of these patterns helps in quickly spotting incorrect variations in exam settings.

Final Answer:
The incorrectly spelt word is Perseverence; the correct spelling is Perseverance.