【正确答案】 D

【答案解析】原文：During the COVID-19 pandemic, pets have only become more important. They have added enjoyment and humor to lives lived indoors. And they keep us company. However, as more people are still working from home because of health restrictions, the animals they keep are causing new problems too. But first, let’ s talk about the good side. For many dogs, the quarantine may seem perfect. Their owners are around all the time, or as we say, 24 hours a day, 7 days a week. So, there might be more time for walks and more treats. Sleeping on the bed at night? Not a problem.题目问的是新的研究表明了什么。新闻中提到随着最近一次满月的开始，一项新的研究表明满月会影响人类的睡眠周期。故答案为D。