Answer:
The correct answer is option A. Line DB
Explanation:
When you write that M is a line, the sign for this would be a line with arrows on both of its end like this : <------------>
Now, due to the fact that lines look like this <------------>, we can cross out option C and D as they both aren't lines but points. Points go like this: ---->
Option B says, "line EB", this can't be true because E corresponds with the letter F, it can't become a line with B hence why the only option true here is choice A.