Correct Answer:  most comfortable

Solution : The correct answer is option 4.

I lost my most comfortable dress.

Explanation:

- Adjectives are words that describe a noun or pronoun.
- The word in the blank will convey more about the subject's dress in the sentence.
- When comparing nouns in a given context, the superlative degree of comparison is typically used to indicate which nouns have the greatest or least degree of the quality being discussed. Three or more nouns or pronouns are compared using this highest level of comparison.

An adjective used in comparisons to indicate something is of the highest degree or is extreme is known as a superlative.

- For example- Tallest, best, most expensive.

- It is obvious from the options provided that "comfortable" is the adjective that best describes the dress.

So we  must use "the," "most," and the adjective in its original form when using them.

Thus, "most comfortable" will be the superlative adjective to use in the omitted blank.