单选题 You know that x is a positive integer. Which of the following statements individually provide(s) sufficient additional information to determine whether the square root of x is also an integer?
Select all such statements.

A、 x is the square of an integer.
B、 The square root of x is the square of an integer.
C、 0＜x＜10

【正确答案】 A、B

【答案解析】Statement (A) can be expressed as x=t², where t is any nonzero integer. In this case, the square root of x equals the square root of t², which is t or -t, depending on whether t is positive or negative, respectively. In either case, the square root of x is an integer. Therefore, statement (A) alone is sufficient. Statement (B) is also sufficient because the square of an integer must also be an integer. Statement (C) indicates that x is a positive integer less than 10, which is not sufficient to determine whether the square root of x is also an integer.