Question : Directions: Three statements are given, followed by four conclusions numbered I, II, III, and IV. Assuming the statements to be true, even if they seem to be at variance with commonly known facts, decide which of the conclusions logically follows from the statements.
Statements:
All birds are ducks.
Some ducks are crows.
All crows are parrots.
Conclusions:
I. Some parrots are birds.
II. Some parrots are ducks.
III. Some crows are birds.
IV. All parrots are birds.

Option 1: Only conclusions I and IV follow

Option 2: Only conclusion II follows

Option 3: Only conclusions I, II and IV follow

Option 4: Only conclusions II and III follow

Correct Answer: Only conclusion II follows

Solution : According to the statements, the following Venn diagram can be drawn –

Let's analyse the conclusions –
Conclusion I: Some parrots are birds – From the above diagram, it is evident that there is no direct relation between parrots and birds. So, no definite relation can be drawn from it. Therefore, this conclusion does not follow.
Conclusion II: Some parrots are ducks – From the above diagram, it is evident that the circles representing parrots and ducks overlap each other and have a part of their area in common. So, from this, it can be concluded that some parrots are ducks. Thus, this conclusion follows.
Conclusion III: Some crows are birds – From the above diagram, it is evident that there is no direct relation between crows and birds. So, no definite relation can be drawn from it. Therefore, this conclusion does not follow.
Conclusion IV: All parrots are birds – From the above diagram, it is evident that there is no direct relation between parrots and birds. So, no definite relation can be drawn from it. Therefore, this conclusion does not follow.

So, only conclusion II follows according to the statements. Hence, the second option is correct.