wireless connectivity solution for sensor

Hi All,

I dont know if im posting my questions in the right place but ill give it a try :)

Im starting to work on a new product and im looking for a transceiver that can transmit to 250m (line of site) with data rate 2KBps . the transmitter need to placed on a human body (wearable) and need works on battery. also i need it to be as small as possible.

I read on several Technology such as sub 1Ghz ( TI CC1350), 2.4Ghz zigbee (802.15.4)(TI CC2520), and a wifi but i didn't succeed to decide what is the best solution for my product requirements.

ill be glad to get your opinion and help.

Thanks