B. animals
Plants have cell walls, bacteria are unicellular and fungi have cell walls too
A dichotomous key helps you identify unknown specimens based on their traits because there are only two options available per trait. Selecting one from the two options (usually contrasting characteristics) from each step leads to smaller and smaller groups until the option is reduced to single and unique trait of an organism.
Considering you need to identify an organism. So, on the top of they key is animal with options: (a) with red blood cells and (b) no red blood cells. The option you will select is no red blood cells and under option b, you’re given two choices again: (a) hard bodies and (b) soft bodies. You’ll select soft bodies, then two options again are given: (a) with shell and (b) without shell. The option you’ll select would be without shell, and so on.
The answer to this question is the sacrum. The sacrum is a triangular bone that forms the base of the spinal column. This bone has a vital role in the skeletal system and also supports the weight of the upper body of a person and this bone and many nerves are inside the sacrum.
Generally, the excretory system of the chickens is actually a biological system that usually removes excess of unnecessary materials from the body of the chicken. A function that eliminates the waste product of metabolism in the body such as liquids or gaseous wastes like urine, sweat and exhalation, these substances are usually toxic for the chicken body. There are only several organs that are considered part of the excretory system. It has also said that the system had a closed relationship with temperature in the body.
