The appropriate answer is 2. an organ system. the first image shows a cell. Cells are the smallest subdivision of an organism considered to be alive or living. The second image represents tissue. Tissue is a collection of specialized cells that have a specific function. Connective and muscular are examples of tissues. The third image shows an organ and this is an anatomical structure that has specialized tissue and a recognizable structural boundary. The fourth image shows an organ system which is a group of organs working together to carry out a specific function such as digestion. The last image represents the organism.