Which of the Following Statements Are True of the D-Xylose

Which of the following statements are true of the D-xylose absorption test?
1) The amount of D-xylose excreted over a 5-hour period is closely correlated with the amount absorbed in the GI tract.
2) Most persons demonstrate plasma levels greater than 300 mg/L in one of the samples collected.
3) Low levels of urine or plasma D-xylose are suggestive of an absorptive defect in the jejunum.
4) High levels of D-xylose are seen in ascites, vomiting, delayed gastric emptying, improper urine collection, and high-dose aspirin therapy.

A) 1, 2, 3, 4
B) 1, 2, 3
C) 1, 3, 4
D) 2, 3, 4