You are employed as a developer at ABC.com. ABC.com has a single Active Directory domain,
named ABC.com.
You are running a training exercise for junior developers. You are currently discussing typographic
grid-units and sub-units.
Which of the following is the topographic grid-defined size for major grid-units?

A.
1px

B.
5px

C.
15px

D.
20px

Explanation:
http://msdn.microsoft.com/en-us/library/windows/apps/hh465362.aspx