Answer: B
- Statement (1): Case 1: 6, 8, 10, 12, 14 (sum 50, mean 10) has median 10. Case 2: 1, 2, 3, 4, 40 (sum 50, mean 10) has median 3. Two different medians, so NOT sufficient. Eliminate A and D.
- Statement (2): there are exactly five integers from 8 through 12 (8, 9, 10, 11, 12). Five different integers in that range must be all of them, so the median is 10. Sufficient.
- Answer B.
Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.: Statement (1) alone is not sufficient: the list 6, 8, 10, 12, 14 has mean 10 and median 10, but the list 1, 2, 3, 4, 40 has mean 10 and median 3.
Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.: Correct. Five different integers from 8 through 12 can only be 8, 9, 10, 11, 12, so the median must be 10. A fixed mean, by contrast, allows very different medians.
BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.: "Neither alone" is false, because statement (2) alone is already sufficient: five different integers from 8 to 12 must be exactly 8, 9, 10, 11, 12, so the median is 10.
EACH statement ALONE is sufficient.: Statement (1) alone is not sufficient: the list 6, 8, 10, 12, 14 has mean 10 and median 10, but the list 1, 2, 3, 4, 40 has mean 10 and median 3.
Statements (1) and (2) TOGETHER are NOT sufficient.: Statement (2) alone is sufficient: five different integers from 8 to 12 must be exactly 8, 9, 10, 11, 12, so the median is 10.
Read every constraint in the stem: "different integers" plus a narrow range can force the whole list, while a mean alone never fixes a median.