You define the following regular expression of currency values: regex tx = new regex("^-?\d+(\.\d{2})?$") You are required to write code that will be used to find whether a string in the variable named Bill matches the regular expression or not. You are also required to use this code as the expression in a conditional statement and need to know which code segment to use. What should you do?（）

A. The tx.Matches（Bill）
B. The tx.Equals（Bill）
C. The tx.Match（Bill）
D. The tx.IsMatch（Bill）