Among the Conclusions of the Many Studies of Technology Diffusion

Among the conclusions of the many studies of technology diffusion is/are:

A) developed economies absorb less foreign technology than developing economies because the former develop more of their own technology.
B) the volume of bilateral trade explains a significant share of the variation in bilateral technology flows.
C) developing countries gain less technology from trade with developed economies than they do from trade links with other developing economies because developed country technology is inappropriate for developing economies.
D) All of the above.
E) None of the above.