2. While selecting the output of the transducer ( if the option is there ) then select 4-20mA if the distance from ouput to your instrument if large ( > 10Meters )+ the environment is noisy ; if it is short then a 0-5VDC is esay to handle.
Select neither, today you can get RS-485 output, we are now in the 21st Centuty.

Erik