A device that combines a receiver and transmitter✓پاسخ درست
A device for matching feed line impedance to 50 ohms
A device for automatically sending and decoding Morse code
A device for converting receiver and transmitter frequencies to another band
توضیح
The name is the definition: trans(mitter) plus (re)ceiver, one unit that does both, typically sharing an oscillator, antenna connector and control circuits. Converting frequencies to another band is a transverter, which is a different device.