Please choose the correct ending to complete the given sentence: Pets and Animals: [header] How to clean and maintain a canary habitat [title] Change the cage liner. [step] To prevent droppings and bacteria from building up, replace the canary's cage liner every day. Newspaper or cob bedding are good liners for canaries.

Ending1: [substeps] Do not use cat litter or wood shavings as cage liner. These can cause breathing problems for canaries. Ending2: Dirt can also build up between the bars of the cage if handled incorrectly. Make sure the bedding is soft and comfortable for the canaries. Ending3: Make sure the newspaper has a large bottom, and avoid paper with too much material in it. If the cage liner has a plastic bag in it, dust the cage of newspaper or cob bedding all the way to the bottom. Ending4: [substeps] Always wipe down the cage liner during your canary's keep-clean yearly breeding season. Also clear out any rocks, grass or sticks from the cage floor, preferably something that has been heavily soiled.

Answer format: ending1/ending2/ending3/ending4