Actually, you want the sound OUTPUT from the TV to go to the INPUT of the speakers. The Bose speakers have a standard RCA stereo input. She MAY have sound output from her TV, though she may not. If you can provide the model of the TV, I can confirm cable needs. Also, if she is using a cable box or some other device as the tuner (what changes the channels), she should just run the sound from there - it most likely has analog audio output which she can use even if she is using a digital connection (such as HDMI) for the video.
Next we need to know exactly what kind of output there is from the TV. If there are RCA outputs (most likely), then the cable you need is a standard RCA male to RCA male pair (they almost always come as a pair).
These ones from Monoprice would work (also available in 6 ft. - I linked to the 12 foot ones), though you can also get them from Radio Shack.
However, the speakers shown aren't going to provide that much of a performance improvement over what is built into the TV.
ETA: we are working with a "line level" (e.g. not amplified) signal - you don't need speaker wire in this case.