Option (b) is correct.

The statements that are so related that they cannot both be false, although they may both be true, are B. "Some metals are gases" and C. "Some metals are not gases."

If statement B is true, it means that there are metals that are gases. This implies that statement C, which states that some metals are not gases, cannot be false because there must be metals that do not fall under the category of gases.

Therefore, the correct answer is option (b) - "B and C only."

विकल्प (b) सही है।

जब दो कथनों में उप-विरोधी संबंध होता है, तो दोनो कथन एक साथ गलत नहीं हो सकते, यद्यपि सही हो सकते हैं।

जो इस प्रकार हैः-