If the absolute value of the equation x + 1 plus the absolute value of X-1 about x equals that a has a real root, then the value range of the real number a is () A a is greater than or equal to 0 B A is greater than or equal to 0 C A is greater than or equal to 1 D A is greater than or equal to 2

If the absolute value of the equation x + 1 plus the absolute value of X-1 about x equals that a has a real root, then the value range of the real number a is () A a is greater than or equal to 0 B A is greater than or equal to 0 C A is greater than or equal to 1 D A is greater than or equal to 2

D