A/T tires will work just fine in light snow.
V-Bar (or Ice Chains) are great in ice.
Also, consider your available clearance before purchasing chains. If you are stock with large tires you may have to go with low profile chains.
When I get to the point of having to chain-up, I always chain all four tires in order to have the pulling effect from the front.
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Regarding tires, my experience is that a wide tire track tends to "plow" with resistance through deep snow and dig in, sometimes to a point of bottoming out to your frame. This can occur even with chains on. Friends with tall thinner track tire cut through deep snow with much less resistance, and tend to stay on top of the snow.
Wide tires do not "float" on snow, they sink in until they compact enough snow to suport the vehicle weight. The goal is less forward resistance in order to continue forward movement. Then again, it depends on the depth of the snow.
In deep snow conditions you must also consider the temperature. During daytime hours, or when the sun is out, the snow tends to become mushy and heavy making it even more difficult to plow through and this increases the opprtunity to become stuck. Then you may have to wait until it refreezes during the evening in order to get out, unless you have a tow vehicle or winch.
When I am off-road in the snow I always carry chains for all four tires as I tend to progress until I can go no further. At that point, it is a little difficult to call for assistance...
Be self limiting and carry the right tools! Spending the night in the snow is not a lot of fun... :shocked