Please choose the correct ending to complete the given sentence: Computers and Electronics: [header] How to choose anti dandruff shampoo [title] Choose shampoos containing zinc pyrithione. [step] Zinc pyrithione is an antibacterial and antifungal agent. Dandruff shampoos containing this ingredient are especially effective at treating dandruff and seborrheic dermatitis caused by malassezia fungi.

Ending1: Zinc sulfate is a byproduct of zinc sulfate. [substeps] Zinc sulfate is a chemical found in root hops. Ending2: [substeps] Zinc pyrithione solutions are best applied over two or three weeks of treatment. Check the labels of all shampoos you use. Ending3: [substeps] Zinc pyrithione shampoos should not be used on infants and children over a year old. These shampoos may dry out your scalp and can cause skin irritation or hair damage. Ending4: [substeps] Popular brands include head & shoulders and jason dandruff relief 2 in 1. [title] Consider tar-based shampoos.

Answer format: ending1/ending2/ending3/ending4