The following is a document I wrote
a number of years ago (about 2007), answering common questions about the LDS
Priesthoods, mainly biblical/theological questions posed from Evangelical works
(e.g. Sharon Banister, For Any Latter-day Saint and Ron Rhodes and
Marian Bodine, Reasoning from the Scriptures with the Mormons). One can
find the document here. Of course, being 7+ years old, there are areas I would
update, but I think it does a good job at answering a number of objections to
LDS claims to authority.