What Prevented Theodore Roosevelt from Achieving the Republican Presidential Nomination

What prevented Theodore Roosevelt from achieving the Republican presidential nomination in 1912?

A) Taft had superior fundraising ability and,by outspending Roosevelt,he prevailed.
B) Taft proved to be more popular with grassroots Republican voters in most of the state primaries.
C) Taft controlled the party caucuses,whose leaders chose the candidate at the national convention.
D) Pro-Taft party officials bribed enough convention delegates to deny Roosevelt the nomination.