Final answer:
The correct answer is d) Are living, as the presence of cells in the samples observed under a microscope indicates they are part of living organisms since cells are the basic unit of life and are a characteristic of all living entities.
Step-by-step explanation:
The answer to the question is: d) Are living. This conclusion is made because all of the samples observed under the microscope have cells, indicating they are living organisms.
The explanation is that the cell theory explains that the existence of cells is a fundamental characteristic of all living organisms. A cell is the basic unit of life, and everything from simple bacteria to complex multicellular organisms like humans is composed of cells. Moreover, cells provide structure and carry out essential life processes that allow the organism to grow, reproduce, and maintain homeostasis.
Bacteria, which are considered living things, are single-celled organisms that have all the properties of life, including metabolism, growth, and the ability to reproduce. Unlike non-living things, which do not have cells or the aforementioned characteristics, any sample containing cells is indicative of life. Accordingly, this fact allows us to classify the observed samples as being part of living beings.
According to the cell theory, all living organisms, from bacteria to humans, are composed of cells, the smallest units of living matter. Often too small to be seen without a microscope, cells come in all sizes and shapes, and their small size allows for a large surface area-to-volume ratio that enables a more efficient exchange of nutrients and wastes with the environment. There are three basic types of cells: archaea, bacteria, and eukaryotes. Both archaea and bacteria are classified as prokaryotic cells, which lack a nucleus and organelles bound by membranes.