Correct Answer: The passenger asks the railway clerk if the train is late.

Solution : The correct choice is the fourth option .

In the conversion to indirect speech, we follow the steps as follows:

• The verb "says" in direct speech is changed to "asks" in indirect speech because the original sentence is a question.
• The tense will not change since the reporting verb is in the present tense.
• The direct question "Is the train late?" is transformed into an indirect question by using "if" or "whether".
• The conjunction "if" is used in the case of yes or no questions.

Therefore, the correct answer is: The passenger asks the railway clerk if the train is late.