Which of the following lines has a positive slope?

• A. A line passing through (2, 1) and (4, 3)
• B. A line passing through (5, 5) and (7, 5)
• C. A line passing through (3, 2) and (1, 4)
• D. A line passing through (0, 0) and (0, 2)

Answer: (A)