阅读短文，选出填入空格最合适的一项： Meat grown from anima…

阅读短文，选出填入空格最合适的一项：

Meat grown from animal cells, rather than taken from slaughtered animals, has attracted heavy investment. Its supporters expect prices to fall quickly, ___ the liquid in which the cells are fed remains costly, and few factories can yet produce the meat on a large scale.