Answer:
A. Average plant height increases with an increase in the concentration of sodium phosphate until the plants reach a maximum possible height.
Explanation:
The graph in the attachment section portrays the average height of plants (cm) on the y-axis plotted against the concentration of sodium phoshate (mg/L) on the x-axis. Based on the observation of the result in the graph, an increase in the concentration of phosphate caused an increase in the average plant height (as depicted by the upward-sloping line).
However, the plant's average height didn't go beyond 35cm despite an increase in concentration of phosphate. This is because the plants has reached a maximum possible height i.e. a height climax. Hence, they cannot grow taller than 35cm no matter the amount of external nutrients (sodium phosphate) supplied.
Therefore, the noticeable trend that can be used to make a conclusion is that average plant height increases with an increase in the concentration of sodium phosphate until the plants reach a maximum possible height.
