What is the excluded value of the rational expression: x-4/6 divided by x+1/7? a. -1 b. 4 c. -7 d. none of the above

For this case we have the following expression:
 ((x-4) / (6)) / ((x + 1) / (7))
 Rewriting we have:
 7 (x-4) / 6 (x + 1)
 We observe that the expression is not defined for the values where the denominator is equal to zero.
 We have then:
 x + 1 = 0
 x = -1
 
 The excluded value of the rational expression is:
 A. -1