Definition: You need to answer a given question containing a blank (_). Your answer must be one of the two objects mentioned in the question, for example "trophy" and "suitcase". Your answer must not contain a word that is not present in the question. Please don't use articles (e.g., the, a) before the answer.
Input: She had just gotten her first period not long ago, so she used a tampon with a string. She struggled to use the tampon because the _ was short.

string