Which of the following situations is inconsistent?

Which of the following situations is inconsistent?a. = 499 + .21 X and r = .75b. = 100 + .9X and r = -.70c. = 20 + 1 X and r = .40d. = -7 – 4X and r = -.90 1. Situation a 2. Situation b 3. Situation c 4. Situation d 5. Situation b & d