Step 1: Fact
Polyethylene terephthalate, PET, is a strong, light and transparent polyester that resists oils, so it is used for bottles of cooking oil.
Step 2: Others
PVC is used for pipes, PS for foam and disposable cutlery, LDPE for films and squeeze bottles.
Final Answer:
PET is used for oil bottles.
\[ \boxed{\text{(D)}\ \text{PET}} \]