Definition: You are given a sentence and a question in the input. If the information provided in the sentence is enough to answer the question, label "Yes", otherwise label "No". Do not use any facts other than those provided in the sentence while labeling "Yes" or "No". There are only two types of valid responses: Yes and No.
Input: Sentence: They saw Robert in front of his house, but he said that he was busy and he could not play with them. 
Question: Why did Greg, Peter, and Lucy walk to the park together?

No.