Please choose the correct ending to complete the given sentence: Pets and Animals: [header] How to make sure newborn puppies receive enough nutrition [title] Opt for the mother's milk whenever possible. [step] A mother's milk has the nutrients necessary for puppies to thrive. A mother will also be able to feed her puppies enough milk without a lot of intervention.

Ending1: When possible, a mother's milk is always the best option. You should only attempt to bottle or syringe feed if the puppies are orphaned or if the mother rejects the litter. Ending2: [substeps] Mix the mother's milk with a few drops of food in a gallon of warm water. [title] Feed your puppies a dry diet. Ending3: To ensure that your puppies get enough milk, it is important to consider more than the amount of milk your puppies need. Some things you may need to watch out for include : [substeps] Excessive milk. Ending4: You should avoid giving milk at inopportune times or when caring for a newborn puppy. For example, if your puppy is pregnant and has a fever that lasts for more than a couple of days, tell your vet.

Answer format: ending1/ending2/ending3/ending4