Many mobile operators already offer a selection of television channels or individual shows, which are sent (1)_____ across their third-generation (3G) networks. In South Korea, television is also sent to mobile phones via satellite and terrestrial broadcast networks, which is far more (2)_____ than sending video across mobile networks; similar broadcasts will begin in Japan in April. Similar mobile-TV networks will also be built in Finland and America, and are being (3)_____ in many other countries. Meanwhile, Apple Computer, which (4)_____ a video-capable version of its iPod portable music player in this October, is (5)_____ a bargain with television networks to expand the (6)_____ of shows that can be purchased (7)_____ viewing on the device. And mobile TV was one of the big (8)_____ at the world"s largest technology fair, the Consumer Electronic Show. (9)_____ all this activity, however, the (10)_____ for mobile TV are unclear. For a start, nobody (11)_____ knows if consumers will pay for it, though surveys suggest they like the idea. One (12)_____ agency of the field, says there will be 125m mobile-TV users by 2010, but many other mobile technologies inspired high hopes and then failed to (13)_____ up to expectations. And (14)_____ people do want TV on the move, there is (15)_____ uncertainty in three areas: technology, business models and the (16)_____ itself. The (17)_____ for mobile TV is vast, in short, but (18)_____ is the degree of uncertainty over how it should actually be put into practice. Most observers do not expect widespread (19)_____ of mobile TV, if it comes at all, until 2008 at the earliest, since building the required ecosystem of technology, partnerships and content will (20)_____ some time.

A. tension
B. status
C. range
D. significance