10 Probability Quiz Easy to Hard Part 2 -- Q8 hypothetical

Q8 on this GregMat quiz

Q8: In a multiple-choice question containing 10 options, students are informed that t of the options are correct. Students must select all correct options in order to receive credit. For what value of t would the student be least likely to receive credit on the question, assuming the student guessed randomly?

The solution for this on the website, when you know how many of the options are to be marked, makes sense. But if you were not informed how many of the options are correct, how would you go about solving this?

Does it make sense to ask the same question – “for what value of t would the student be least likely to receive credit on the question, assuming the student guessed randomly?”

I think the students would need to know the number of questions, otherwise they can guess any number so there’s no point choosing a value of t