21. Unlike the original National Museum of Science and Technology in Italy, where the models are encased in glass or operated only by staff members, the Virtual Leonardo Project, an online version of the museum, encourages visitors to "touch" each exhibit, which thereby activates the animated functions of the piece.
A. exhibit, which thereby activates
B. exhibit, in turn an activation of
C. exhibit, and it will activate
D. exhibit and thereby activate
E. exhibit which, as a result, activates
A. exhibit, which thereby activates
B. exhibit, in turn an activation of
C. exhibit, and it will activate
D. exhibit and thereby activate
E. exhibit which, as a result, activates
