Read the given statements and conclusions carefully. Assuming that the information given in the statements is true, even if it appears to be at variance with commonly known facts, decide which of the given conclusions logically follow(s) from the statements.
Statements:
I. All engines are keys.
II. Some keys are trains.
Conclusions:
I. Some keys are engines.
II. Some trains are engines.

​Statements:
I. All engines are keys.
II. Some keys are trains.

​Conclusions:
I. Some keys are engines. (True, since all engines are keys, it is definitely true that some keys that are engines exist).
II. Some trains are engines. (False, there is no direct relation between trains and engines).

So, Only conclusion I follows.

Thus, correct option is (d).