Researchersfromthefacultyofcivilengineering，UniversitiTeknologiMARAinMalaysiahavesuccessfullydevelopedanenvironmentallyfriendlyversionofbuildingconcertcalledgreen-mixconcrete．Intheproject，researchersintroducedagreen

　　Researchers from the faculty of civil engineering，Universiti Teknologi MARA in Malaysia have successfully developed an environmentally friendly version of building concert called green-mix concrete．

　　In the project，researchers introduced a green concrete that is designed and made using conventional but particularly replaced with suitable waste and recycled materials to achieve acceptable performance，economics and sustainability．

　　When it comes to build structures，developers have the advantage of choosing from a wide range of materials to use．Generally，the decision on material choice depends on several factors including cost and performance for specific applications．

　　Due to growing interest in sustainable （可持续的）development and various pushing measures provided by the government of Malaysia，the key players in the construction industry are motivated more than ever before to use materials that are sustainable or in such a way that environment impact is minimal．

　　In 2009，the Malaysian government launched the green building index（GBI） to encourage the construction of buildings using green technology，and introduced pushing measures for owners to obtain the GBI certificate for new or exiting buildings．There have been efforts to reduce air pollution and concrete has an important role to play．

　　The new concrete can be produced using materials as one of its components．Green concrete can also developed using various production processes that are not harmful to the environment．The use of recycled or waste materials can be considered sustainable as they can reduce costs and raw materials．

　　24．Which of the following best describes green-mix concrete？___

　　A．Low carbon and costly．

　　B．Green and fashionable．

　　C．Money-saving and sustainable．

　　D．Sustainable and conventional．

　　25．Who mainly decides the choice of building materials？___

　　A．Researchers．

　　B．Developers．

　　C．Cer