, where should the capillaries and lymphatic vessels be placed tomaximize the absorption of nutrients from food

They should be placed in the small and large intestine.

Explanation:

The small and large intestine is the part of our digestive system that absorbs the nutrients from food. Previous to this step, the food went through the mouth, the esophagus, and the stomach. In those places, it was processed so that the intestines could absorb the nutrients from the food easily/

For nutrients to be absorbed, they should be in stretch contact with the intestines' walls where the smallest arteries, which are called capillaries, are present and will take the nutrients into its interior where the blood is. Also, the intestines have lymphatic vessels. These ones will protect our body from any antigen since they are part of our immune system.