Which organelle is most like a miniature stomach?

The correct answer is Lysosomes.

Lysosomes are membrane-bound organelles found in the cytoplasm of animal cells. They contain hydrolytic enzymes that help digest waste materials and worn-out cell parts. Lysosomes are also involved in the process of autophagy, which is the self-destruction of damaged or unwanted cells. In this sense, lysosomes can be thought of as miniature stomachs because they are responsible for breaking down and digesting material within the cell.