To assess the reliability of the sentences, we need to consider the context and whether the statements are based on verifiable facts or are subjective interpretations.
A. Unreliable - The characterization of the environment as "unpleasant and unfriendly" is subjective and could vary depending on individual experiences or perspectives. Without specific evidence or sources, this statement is not reliable.
B. Unreliable - Similar to the first sentence, the claim that "none of the pioneers liked summer" is a generalization and subjective in nature. It lacks evidence and is based on individual feelings, making it unreliable.
C. Reliable - This sentence presents a specific action taken by the pioneers (building underground homes) that can be verified through historical records. If supported by documentation or historical context, it is likely to be considered a reliable statement.
In summary:
- Sentence A: Unreliable
- Sentence B: Unreliable
- Sentence C: Reliable