18.In many parts of America, a surprising number of folksy, regional, and rural expressions have developed _______ the years and, even today, are heard and used by many American speakers of English. A large number of these _______ sayings also live in the memories of today’s citified adults who can remember hearing their grandparents use these sayings frequently.
(A) in; unbelievable
(B) over; unfastened
(C) during; figurative
(D) through; colorful