Definition: In this task, you will be presented with a passage and have to answer a question based on your understanding of the events inferred from the passage. Try to find the best answer that is most likely to fill in "_". Note that the URLs in the text have been replaced with [Link].
Input: (CNN) The sooner babies get their own rooms, the longer they'll sleep on average, according to a new study that breaks with the recommendations of the American Academy of Pediatrics. Analyzing surveys from 230 first-time mothers at Penn State, Dr. Ian Paul, a pediatrician, found that babies slept for longer stretches if they didn't sleep in the same bedroom as their parents. At 4 months, babies who slept alone had the longest stretches of uninterrupted sleep -- by about 45 minutes, on average -- though they slept about the same amount of time as babies who slept in their parents' rooms.Babies who slept in their parents' rooms slept for shorter periods, a new study findsA leading pediatrics group recommends room-sharing with infants until 1 year 
 Question:The _ sample was also "not terribly diverse in terms of socioeconomic or racial diversity," which could cast doubts upon how much this research speaks for the general population, Moon said.
Output:
Penn State