The dependent variable would be anything that is not consistent. So outside factors such as how much sun and the environment that the plant is contained in.
By looking for the presence of the germ layers and the primitive gut in the embryo
The continual input of energy, mostly from sunlight, sustains the process of life. Sunlight allows plants, algae and cyanobacteria to use photosynthesis to convert carbon dioxide and water into organic compounds like carbohydrates. This process is the fundamental source of organic material in the biosphere. There are a few exceptions to this, such as ecosystems living around hydrothermal vents on the ocean floor, which derive their energy from the chemical compounds such as methane and hydrogen sulfide. In either case, the overall productivity of an ecosystem is controlled by the total energy available.
I think it’s A
Hopefully this helps!!
A ruler will not be needed due to having a graduated cylinder which can help measure the volume of liquids
