Statements : All doors are buses. All buses are leaves. No leaf is a flower. Conclusions : I. No flower is a door. II. No flower is a bus. III. Some leaves are doors. IV. Some leaves are buses.

The correct answer is A. None follows.

The first statement is “All doors are buses.” This means that every door is a bus. The second statement is “All buses are leaves.” This means that every bus is a leaf. The third statement is “No leaf is a flower.” This means that no leaf is a flower.

From the first statement, we can conclude that all doors are buses. From the second statement, we can conclude that all buses are leaves. From the third statement, we can conclude that no leaf is a flower. However, we cannot conclude anything about the relationship between doors and flowers. It is possible that there are no doors that are flowers, but it is also possible that there are doors that are flowers. Therefore, none of the conclusions follow.

Here is a more detailed explanation of each option:

• Option A: None follows. This is the correct answer. As explained above, none of the conclusions follow.
• Option B: Only I and II follow. This is incorrect. Conclusion I follows, but conclusion II does not follow.
• Option C: Only II and III follow. This is incorrect. Conclusion II follows, but conclusion III does not follow.
• Option D: Only II, III and IV follow. This is incorrect. Conclusion II follows, but conclusions III and IV do not follow.
• Option E: All follow. This is incorrect. None of the conclusions follow.