The function f(x) appears to be selective for the concept of "tennis". Words that are associated with tennis tend to have output values close to 1, indicating a strong association. For example, the word "tennis" itself has an output value of 0.9732, which is very close to 1. On the other hand, words that are not related to tennis, such as "Eiffel Tower" or "Alps", have much lower output values. Therefore, f(x) seems to be selective for the concept of tennis and assigns higher values to words that are more closely related to this concept.