Final answer:
The word that correctly fills the blank is 'fewer' as it is used for items that can be counted, like students in this context.
Step-by-step explanation:
The correct word to fill in the blank is 'fewer'. 'Fewer' refers to items that can be counted, like students, whereas 'less' refers to a quantity of something that cannot be counted. For example, 'I have fewer assignments than my roommate, and she has less time than I do.' In the context of the university having an amount of students from other countries that can be counted, 'fewer' is the appropriate choice.