Variable a is 4 more than variable b. Variable a is also 1 less than b. Which of the following pairs of equations best models the relationship between a and b?

(4 points)

A a = b + 4 a = b – 1

B a = 4b a = b + 1

C b = a + 4 b = a – 1

D b = 4a b = a + 1