What is the extension for the file containing data for ASO applications?

A.
.pag

B.
.dat

C.
.txt

D.
.aso

E.
.fil

Explanation:
http://www.mi-oaug.org/Presentations09/Internal%20Workings%20of%20EssbaseASO%20&%20BSO%20Secrets%20Revealed%20MIOAUG.pdf