Please choose the correct ending to complete the given sentence: Pets and Animals: [header] How to fit a martingale collar [title] Use a soft tape measure or piece of string to measure your dog's head. [step] Measure the largest part of your dog's head and the middle of their neck. If your dog's head is larger than their neck, you'll need a collar that can fit comfortably over their head.

Ending1: Measure your dog's neck, then measure directly where it starts to curve up from their skull. [substeps] With a 23-inch (23-cm) collar, your dog's head should be about 3.2 inches (3.7 cm) long. Ending2: If their neck is larger than their head, you'll need a collar that fits comfortably around their neck. [substeps] Add 2 " to the largest measurement to allow for growth. Ending3: Wrap a large piece of rope around their neck or use a tape measure to measure your dog's head. [title] Make a small mark where you want your necklace to end. Ending4: [title] Double check the length of the collar. [step] You want your desired collar to measure about 12 inches (30.

Answer format: ending1/ending2/ending3/ending4