Read the given statements and conclusions carefully. Accept the information given in the statements as correct, even if it seems to be different from the commonly known facts and decide which of the given conclusions follows the logic.
Statement:
I. All bikes are cars.
II. All cars are aeroplanes.

Conclusion:
I. All bikes are aeroplanes.
II. Some aeroplanes are cars. ​​

Statement:
I. All bikes are cars.
II. All cars are aeroplanes.

Since all bikes are cars, and all cars are aeroplanes, it logically follows that all bikes are also aeroplanes. Conclusion (I) is follow.
II. Some aeroplanes are cars. ​​

Since all cars are aeroplanes, it is also true that some aeroplanes are cars. Conclusion (II) is follow

Thus, the correct option is (b) Both conclusions (I) and (II) follow.