A．some NBAC members hesitate to ban human cloning completely
B．a law banning human cloning is to be passed in no time
C．privately funded researchers will respond positively to NBAC"s appeal
D．the issue of human cloning will soon be settled

A．pushing information on the Web is essential to Internet commerce
B．interactivity, hospitality and security are important to online customers
C．leading companies began to take the online plunge decades ago
D．setting up shops in silicon is independent of the cost of computing power

A．how to make the workers more productive
B．impossible factors leading to greater efficiency
C．to what extent more money leads to greater productivity
D．how to make workers" jobs more interesting