The correct answer is A. one-dimensional.
A one-dimensional graph is a graph that has only one axis. The data points in a one-dimensional graph are represented by points on a line.
A two-dimensional graph is a graph that has two axes. The data points in a two-dimensional graph are represented by points in a plane.
A three-dimensional graph is a graph that has three axes. The data points in a three-dimensional graph are represented by points in space.
The figure shows a line graph, which is a type of one-dimensional graph. The line graph shows the relationship between two variables, time and temperature. The data points in the line graph are represented by points on a line.
The other options are incorrect because they do not describe the figure correctly. Option B is incorrect because the figure shows a line graph, which is a type of one-dimensional graph. Option C is incorrect because the figure shows a line graph, which is not a type of three-dimensional graph. Option D is incorrect because the figure shows a line graph, which is a type of graph.