An old man lived in the village. He was one of the (1) ______ unfortunate people in the world. The whole village was tired (2) ______ him; he was always gloomy, he (3) ______ complained and was always in a bad mood. The (4) ______ he lived, the more vile he was becoming and the more (5) ______ were his words.

Select the most appropriate option to fill in blank number 1.

The correct option to fill in blank number 1 is "most".

Step-by-Step Explanation:
1. We need to identify the correct word to fill in blank (1) in the sentence: "He was one of the (1) ______ unfortunate people in the world."
2. In English grammar, when comparing more than two things or expressing the highest degree of a quality, we use the superlative degree of an adjective.
3. The adjective in the sentence is "unfortunate". Since "unfortunate" has three syllables (un-for-tu-nate), its superlative degree is formed by placing the adverb "most" before it, making it "the most unfortunate".
4. Let's analyze the given options:
- "maximum": This refers to the greatest amount or quantity possible and is not used to form the superlative degree of an adjective.
- "utmost": This means most extreme or greatest, but it is not grammatically used to modify "unfortunate" in this structure.
- "most": This is the correct grammatical adverb to form the superlative degree of "unfortunate".
- "main": This means chief or principal, which does not fit the context or grammatical structure here.
5. Therefore, "most" is the most appropriate option to complete the phrase "one of the most unfortunate people".