Which symbol is used in mathematics to indicate equality?

The symbol used in mathematics to indicate equality is the equal sign, which is represented by the symbol "D." This symbol asserts that the values on either side of it are the same or equivalent. For example, in the equation "2 + 3 = 5," the equal sign shows that the left side (2 + 3) is equal to the right side (5), establishing a relationship of equality between the two expressions.

Understanding the role of this symbol is fundamental in mathematics, as it serves as a foundational concept in equations and expressions, allowing mathematicians to communicate that two quantities or expressions have the same value. The other symbols listed—addition (+), subtraction (-), and multiplication (*)—represent operations rather than a statement of equality, which is why they are not correct in this context.