To solve this question, the user needs to have knowledge of English grammar rules, particularly the correct order of adjectives.

In this sentence, two adjectives are used to describe the house - "comfortable" and "little". The correct order of adjectives in English is: opinion, size, age, shape, color, origin, material, purpose.

The option that follows this order is:

D. a comfortable little

Option A is incorrect because it is in the wrong order.

Option B is incorrect because it reverses the order of the adjectives.

Option C is incorrect because it also reverses the order of the adjectives.

Therefore, the answer is: D. a comfortable little.