Answer: THIRD OPTION.
Step-by-step explanation:
For this case it is important to know that by definition, there are three possible cases for the solution of a System of equations. These are shown below:
1. If the lines intersect each other, then the System of equations has ONE SOLUTION.
2. If the lines are parallel, then the System of equations has NO SOLUTION.
3. If the two equations are the same line, then the System of equations has INFINITELY MANY SOLUTIONS.
Observe the graphs attached in the exercise.
You can notice in the third graph that the "line a" and the "line b" are exactly the same line.
Therefore, based on the explained before, you can conclude that the third graph given in the exercise contains a System of equations with Infinitely many solutions.
