Which of the Following Is True of Microblogging

Multiple Choice

Which of the following is true of microblogging?

A) Entries in a microblogging site appear in chronological order.
B) All posts on a similar topic include a keyword prefixed by a @, which is called a mashup.
C) Entries in a microblogging site have no space constraints.
D) Users themselves have added their own conventions to make microblogging more useful.