President Herbert Hoover's progressive reforms included all of the following except?supporting a plan for tax reductions in the lower-income...

This appears to be a question from a test bank for Tindall
and Shi's America: A Narrative History. You can find the answer in
Ch. 27 in a section entitled "Hoover in Control."  the answer to this is 3.  This can be
found in the book and it also makes sense when you think about Hoover's own political
philosophy.  Hoover did not believe in the idea of the government simply giving money to
low-income people.  This would have gone against his belief in "rugged
materialism."

Giving tax breaks to lower-income people
would have been fine.  Lower taxes go with conservative values and they reward poorer
people who work.  Hoover also took action against patronage, refused to support "Red
hunts" and was personally liberal on racial issues.  In addition to pushing for support
for Howard University, he defended his wife's right to entertain the wife of Oscar
DePriest, the first ever black Congressman from the
North.

For these reasons, 3 is the only right
answer.