Please choose the correct ending to complete the given sentence: Food and Entertaining: [header] How to cook bone marrow [title] Preheat the oven to 450 ° f (232 ° c). [step] Adjust your oven rack so it's in the center of the oven. [title] Arrange 2 to 3 pounds (0.9 to 1.4 kg) of marrow bones on a sheet.

Ending1: [step] Make sure they have some room to expand during cooking. The bones should stand straight up and they should be symmetrical. Ending2: [step] Get out beef marrow bones and place them on a rimmed baking sheet such as a jellyroll pan. [substeps] Spread the bones in a single layer. Ending3: [step] The bones should be facing up, but there should still be enough room inside to fit the bone. [title] Form a ball of bone in your hand. Ending4: [step] Place all 6 bone bones in the center of a greased 9 x 13-inch pan. Cook them on a medium heat until the bones become translucent, which should take about 3 to 4 minutes.

Answer format: ending1/ending2/ending3/ending4