Hi Edmond,
Do you already have sensors, and you want to select NI data acquisition tools? Or do you also need to select the sensors?
Although the available acquisition tools can inform your sensor selection, I'd imagine that usually it's better to focus on finding the best sensors for your application, and then confirm that you can acquire suitable DAQ devices based on that choice (not the other way around).
Sometimes it might be that you choose a 2nd-choice sensor because it is much easier/cheaper to acquire the data, but you'd still need to check for the 1st-choice sensor first...
If you have a list of sensors (or types) an NI sales representative might be a good person to ask for suggestions.
Your question at present is very general.