We have to select a plastic film for use as a food wrap.  PVC stands for polyvinyl chloride.  It is a widely used plastic polymer, expecially for piping and conduits.  In order to be made pliable for use as a wrap, plasticizers have to be added and these can leak out onto food products.  PP stand for polypropylene, another plastic polymer.  It is commonly used as protective plasic sheeting but I'm not sure it makes as effective a thin film for food use as the other two.  I don't think it is able to cling to food containers like the other two, either.  Saran wrap was originally made from PVC but fears of food absorbing the chemicals has caused other alternatives to be found.  Current food wraps use various forms of polyethylene as their main component as it utilizes less chemicals but still maintains an appealing cling to food containers.  So I would choose Saran wrap as the food wrap of choice for strawberries.