I think 100 years from today there will be flying cars which people will park __27__ thebuildings. If this happens, there won’t be any more traffic jams! Tourism in space will be verypopular, and space shuttles will take people _28_ exciting vacations to the Moon. I believe thatmost houses will be environmentally friendly as we’ll only use alternative sources of energy__29__ wind and solar power. In the future, I think robots will __30__ most of our housework, solife will be easier.
27.
(A) at the bottom of
(B) in relation to
(C) on top of
(D) with reference to