In the following question, four words are given, out of which one word is incorrectly spelt. Select the incorrectly spelt word.

Introduction / Context:
This is another spelling-identification question. You must pick the one incorrectly spelt word from the four options. All four are reasonably common in written English, particularly in descriptive and scientific contexts. Spelling questions check your attention to detail and your familiarity with standard English forms. Correct spelling is important not only in exams but also in professional communication and formal writing.

Given Data / Assumptions:

The options are “fabulous”, “gorgeous”, “heterogeneous” and “inocuous”.
Three words are correctly spelt; one contains a spelling mistake.
We assume standard British or Indian English spellings.

Concept / Approach:
The standard spelling for the word meaning “harmless” is “innocuous”, with a double “n” and an extra “c”: i-n-n-o-c-u-o-u-s. The option given, “inocuous”, is missing one “n” and one “c”, so it is incorrect. The other words are correctly spelt: “fabulous” (wonderful), “gorgeous” (extremely beautiful) and “heterogeneous” (consisting of different kinds). The approach is to mentally compare each option with its known correct dictionary form or with familiar exposure through reading.

Step-by-Step Solution:
Step 1: Examine “fabulous”. This is a common adjective meaning wonderful or extraordinary; the spelling f-a-b-u-l-o-u-s is standard and correct. Step 2: Examine “gorgeous”. This is correctly spelt as g-o-r-g-e-o-u-s and is widely used to describe something very beautiful. Step 3: Examine “heterogeneous”. This word, used in science and statistics, is accurately spelt h-e-t-e-r-o-g-e-n-e-o-u-s. Step 4: Examine “inocuous”. The intended word appears to be “innocuous”. Step 5: The correct spelling is “innocuous” with double “n” and including the “c” after “o”: i-n-n-o-c-u-o-u-s. Step 6: Since “inocuous” is missing letters and does not match the standard form, it is the incorrectly spelt word.

Verification / Alternative check:
Consider example sentences: “The medicine is quite innocuous and has no side effects.” If you try to spell it as “inocuous”, most spell-checkers would mark it wrong. Standard dictionaries list only “innocuous” as the accepted spelling. By contrast, “fabulous show”, “gorgeous scenery” and “heterogeneous mixture” all use the correct spellings that match the options given. This comparison confirms that “inocuous” is the single incorrect spelling among the four words.

Why Other Options Are Wrong (as answers):
Fabulous: Correct spelling, commonly used to mean wonderful or excellent.
Gorgeous: Correct spelling, used widely to describe great physical beauty or impressive appearance.
Heterogeneous: Correct spelling, used to describe a mixture or group made up of different kinds or types.

Common Pitfalls:
Long words with multiple vowels and consonant clusters, such as “heterogeneous” or “innocuous”, often confuse learners. Many students assume the longest, most complicated-looking word must be wrong. However, exam-setters frequently hide the error in what appears to be the simplest or least suspicious option. To avoid mistakes, do not guess based only on word length. Instead, read widely and pay attention to the spelling of words you encounter. Over time, your memory of correct patterns (like double “n” in “innocuous”) will become strong enough to guide you quickly in such questions.

Final Answer:
Correct answer: inocuous.