Select the option that represents the correct order of the given words as they would appear in an English dictionary.
1. Infant
2. Indolent
3. Inert
4. Infamous
5. Inefficient
6. Ineffable

To arrange the words in an English dictionary, we compare them letter by letter from left to right:
7. All words start with the prefix In-. Let's compare the 3rd letter of each word:
* Infant (f)
* Indolent (d)
* Inert (e)
* Infamous (f)
* Inefficient (e)
* Ineffable (e)

8. Alphabetically, 'd' comes first. Therefore, 2. Indolent is the first word in the sequence.
9. Next, we compare the words with the 3rd letter 'e': 3. Inert, 5. Inefficient, and 6. Ineffable. Comparing their 4th letters:
* Inert (r)
* Inefficient (f)
* Ineffable (f)
* Since 'f' comes before 'r', we compare 5 and 6 by their 6th letter (as both share 'Ineff'):
* Inefficient (i)
* Ineffable (a)

* 'a' comes before 'i', so 6. Ineffable comes before 5. Inefficient. Then comes 3. Inert.
* Sequence so far: $2,6,5,3$

10. Finally, we compare the remaining words with the 3rd letter 'f': 1. Infant and 4. Infamous. Comparing them from the 4th letter onwards:
* Infamous (m)
* Infant (n)
* 'm' comes before 'n', so 4. Infamous comes before 1. Infant.
* Final Sequence: $2,6,5,3,4,1$

This matches the sequence given in Option C.