The question has multiple choices
a)
Advanced filters
b)
Cross-domain tracking
c)
Event tracking
d)
Custom Dimensions
The answer is b) Cross-domain tracking
Sometimes
called site linking, this feature makes it possible for Google analytics to
see sessions on two related websites as a single session by a single user. To
track these sessions, Google analytics collects Client-Id value stored in
cookies. In the case of multiple domains, the Client-Id value has to be carried
from one domain to another.
