The correct answer is: Only II follows.
The first statement is “Some trains are roads.” This means that there is at least one train that is also a road. The second statement is “No road is jungle.” This means that there is no road that is also a jungle. The third statement is “All flowers are jungles.” This means that all flowers are also jungles.
From the first statement, we can conclude that some trains are roads. However, we cannot conclude that all trains are roads, because the statement only says that there is at least one train that is also a road. From the second statement, we can conclude that no road is a jungle. However, we cannot conclude that no jungle is a road, because the statement only says that there is no road that is also a jungle. From the third statement, we can conclude that all flowers are jungles. However, we cannot conclude that all jungles are flowers, because the statement only says that all flowers are also jungles.
Therefore, the only conclusion that follows from the given statements is that some trains are jungles. This is conclusion II.
The other conclusions are not valid. Conclusion I is not valid because it does not follow from the first statement. The first statement only says that there is at least one train that is also a road, but it does not say that there is at least one flower that is also a train. Conclusion III is not valid because it does not follow from the third statement. The third statement only says that all flowers are jungles, but it does not say that there is at least one flower that is also a train. Conclusion IV is valid because it follows from the second statement. The second statement says that no road is a jungle, and this implies that no road is a flower.