Question

the received and transmitted simultaneously. any sound that winston made, above the level of a very low whisper, would be picked up by it; moreover, so long as he remained within the field of vision which the metal plaque commanded, he could be seen as well as heard\ (5)

Explanation:

This appears to be a fill - in - the - blank question from a literary text (likely from 1984 by George Orwell). The word that fits here is "telescreen". In the context of the novel, the telescreen is a device that can both receive and transmit, allowing the Party to monitor people.

The text is from 1984, and the device that can receive and transmit simultaneously to monitor Winston is the telescreen.

Answer:

telescreen