What signifies that a number is part of the sequence of squares?

A number is part of the sequence of squares if it is the product of a number multiplied by itself. This definition directly corresponds to how square numbers are generated: for any integer ( n ), the square of that integer is represented as ( n \times n ) or ( n^2 ). Thus, square numbers in the sequence are 1 (1x1), 4 (2x2), 9 (3x3), 16 (4x4), and so forth. This characteristic distinguishes square numbers from other types of numbers, making option B the correct choice.

The other options do not align with the definition of square numbers. For instance, while prime numbers are integers greater than 1 that have no positive divisors other than 1 and themselves, they do not necessarily fit the definition of being squared. Additionally, the multiplication of two different numbers corresponds to products but not specifically squares, which require the same number multiplied by itself. Lastly, the Fibonacci sequence involves numbers that form a specific recursive pattern that does not pertain to perfect squares. Thus, option B accurately highlights the defining property of square numbers within the context of this question.