How to save frequent flyer miles about to expire<br>Shop through an airline portal. Almost every airline has online malls or portals where you can shop. You'll earn extra miles on your purchases, and the clock will " reset, " so you won't lose any miles because of inactivity.

Based on that paragraph can we conclude that this sentence is true?
All airlines have online malls or portals for shopping.

Available choices: a). Yes. b). It's impossible to say. c). No.
c).