[单选题]Choose the closest paraphrased version after each of the following sentence or italicized part.This [not living in memories] is not always easy; one's own past is a gradually increasing weight.（） A …as they get older, people find it harder to remember their past. B …as they grow older, people accumulate more experience. C ...to old people, their past is becoming more important. D …to old people, their past is becoming a heavy burden.