在 Where do you think 后面应该用陈述句语序。例如: Where do you think (that) we should eat ? 你认为我们该去哪儿吃饭?(摘自《韦氏高阶英汉双解词典》p.2184)
do you think 不能作为插入语。所以,“Where do you think is the best place to keep food safe from bears?”应该改为:
Where do you think the best place to keep food safe from bears is?