Option (d) is correct.

Statements B and D are related in such a way that they both cannot be false, although they may both be true.

Statement B, "Some animals are birds," means that there is at least one animal that is also a bird.

Statement D, "Some animals are not birds," means that there is at least one animal that is not a bird. It is possible for both of these statements to be true at the same time.

Statements A and C, are mutually exclusive and cannot both be true at the same time. Statement A, "All animals are birds," contradicts Statement C, "No animals are birds."

विकल्प (d) सही है।

जब दो कथनों के मध्य उप-विरोधी का सम्बन्ध हो तो वे आपस में सत्य हो सकते है लेकिन असत्य नहीं हो सकते है। नीचे दिए गए विरोध के परंपरागत वर्ग के अनुसार “कुछ जानवर पक्षी होते हैं” [I] प्रतिज्ञप्ति और “कुछ जानवर पक्षी नहीं होते हैं” [O] प्रतिज्ञप्ति सही उत्तर हैं।