Read this passage, study the graph, and then answer the question.

Graphs are useful for presenting data. One type of graph is a line graph.

The line graph below was presented on p. 2 of this lesson. It shows measurements of light, carbon dioxide, water, and temperature. All measurements were taken in the same greenhouse where many plants were being grown.

The y axis has an unusual label. It doesn't have numbers. This is because levels of light, carbon dioxide, water, and temperature would need different scales and units. However, it does show relative changes over time. For example, notice that the carbon dioxide level goes down significantly in the middle section of the day.

1. What is the most logical reason that the carbon dioxide level went down during the middle of the day? Use the graph to help you decide. It will also be helpful to think about what you have learned in previous units.

(1 point)
Responses

The carbon dioxide level decreases in the middle of the day because the light level goes up, which allows the plants in the greenhouse to perform photosynthesis and remove carbon dioxide from the air.
The carbon dioxide level decreases in the middle of the day because the light level goes up, which allows the plants in the greenhouse to perform photosynthesis and remove carbon dioxide from the air.

The carbon dioxide level decreases in the middle of the day because the greenhouse was flooded with steadily increasing levels of water.
The carbon dioxide level decreases in the middle of the day because the greenhouse was flooded with steadily increasing levels of water.

The carbon dioxide level decreases in the middle of the day because the temperature suddenly drops and stays below the freezing point.
The carbon dioxide level decreases in the middle of the day because the temperature suddenly drops and stays below the freezing point.

The carbon dioxide level decreases in the middle of the day because there is no light in the greenhouse, so photosynthesis can't be performed.
The carbon dioxide level decreases in the middle of the day because there is no light in the greenhouse, so photosynthesis can't be performed.

The most logical reason that the carbon dioxide level went down during the middle of the day is because the light level goes up, which allows the plants in the greenhouse to perform photosynthesis and remove carbon dioxide from the air. This is supported by the graph, which shows a correlation between the light levels and the carbon dioxide levels in the greenhouse.