The correct answer is: none.
The word “none” is used to refer to a number or amount of zero. In this case, the speaker is saying that they did not have any questions for the lecturer. This could mean that they understood the material well, or that they were not interested in the topic.
The word “no” is also used to refer to a number or amount of zero. However, it can also be used to express negation or disagreement. In this case, the speaker could be saying that they did not have any questions, but they could also be saying that they did not want to ask any questions.
The word “some” is used to refer to a number or amount that is greater than zero but less than a specific number. In this case, the speaker could be saying that they had a few questions, but not many.
The word “any” is used to refer to a number or amount that is greater than zero. In this case, the speaker could be saying that they had at least one question, but they could also be saying that they had many questions.
I hope this explanation is helpful!