C) Compostable zip lock bag. It is usually used for daily products like cloths, or cosmetic tools etc. For this usage, usually transparent bags or frosted bags are preferred for people to easy tell the inside content. I have to say, frosted one is best choice because you could use both PLA+PBAT material to make the bag soft touch. The solution to make transparent compostable bag is using 100% PLA material, then the bags are a little bit rigid, more easier to break and the soft bags. Below image show you how they look.