Question about the implicitly-sorted-rule of key

[navegador5]

the document mentioned:

Insertion order of record keys does not affect equality of records, 
because there's no way to observe the original ordering of the keys, as they're implicitly sorted:

what is the sort rule? A or B ?

A. first sort index-like keys : ("1", "15", "6"... ), then others ["aa","bb","cc"]_ B.just sort them together : [1,15, 6, "aa","bb","cc"]