Gelatin is often used as an ingradient in the manufacture of ice-cream. The reason is

The food product known as gelatin is transparent, colorless and flavorless. It is made from collagen and is frequently used in food and pharmaceuticals as a gelling agent. 

When it is added to Ice-creams, it acts as an emulsifier (an additive which is used to mix two liquids). It gives the Ice-cream its texture and keeps it fresh

Hence the correct option is (B).