The following data sufficiency problems consist of a question and two statements, labeled (1) and (2), in which certain data are given. You have to decide whether the data given in the statements are sufficient for answering the question. Using the data given in the statements plus your knowledge of mathematics and everyday facts (such as the number of days in July or the meaning of counterclockwise), you must indicate whether.
Is the positive integer y a prime number ？（）
(1) 80＜y＜95
(2) y=3x+1, where x is a positive integer
A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D. EACH statement ALONE is sufficient.
E. Statements (1) and (2) TOGETHER are NOT sufficient.
参考答案：C
解析：
alone is insufficient because the range mentioned contains both prime numbers (e.g., 83, 89) and nonprime numbers. (2) alone is insufficient because it provides both prime (e.g., 7, 13) and nonprime values for y. If the statements are combined, they are sufficient, because none of the numbers that meet both criteria (82, 85, 88, 91, and 94) are prime numbers (91 is 13×7).