When creating a regression analysis for electric car sales based on fuel prices, what would the XY diagram resemble?

The correct choice illustrates the relationship between fuel prices and electric car sales through a trendline in a scatter plot format. In regression analysis, we aim to identify and visualize the correlation between two variables—in this scenario, fuel prices and electric car sales.

When constructing the XY diagram, fuel prices are placed along the X-axis, while electric car sales are represented on the Y-axis. The trendline that emerges from the data points indicates the general direction or pattern of the relationship between these two variables. A positive or negative slope of the trendline can signify whether higher fuel prices correlate with increased electric car sales or not. This visualization is fundamental in regression analysis, as it helps to predict future sales based on changing fuel prices, thereby offering insights into consumer behavior and market dynamics.

The other options describe scenarios that do not effectively represent the regression analysis. A scatter plot with no trendline fails to convey the relationship between the variables, while a constant vertical or horizontal line would imply that one variable does not affect the other, which would not be the intended outcome of a regression analysis.