Protestant might believe all kinds of things. They frequently believe that the Latin Vulgate is heretical, accusing it of being deliberately changed to satisfy a more pagan interpretation of Christianity. They believe that Catholics deify Mary, considering her to be somehow made to be part of the Trinity, and so warping Christianity to be in line with some pagan (including ancient Egyptian) cults who have a deistic trinity consisting of a Father/Mother/Son. They also believe that graven images of God amount to idolatry, so crucifixes with a corpus are no-go. Some see that praying at statues is akin to idolatry also. The above does not really include Lutherans or Anglicans, who generally have a better understanding of basic theology and so are less easily deluded. Some Protestants are offended by Easter eggs, because they have pagan origins, and others argue against various aspects of how Catholics celebrate Christmas, and more creative people come up with arguments against pretty much everything else, because it is against their business model to lose their flock to Catholicism.

Now most of these accusations are Masonic and Jєωιѕн in origin, because in their cult a lot of emphasis is given to study of ancient religions (including тαℓмυdic Judaism) and this knowledge is used to discredit Catholicism.

Traditional Catholics can usually give good refutations to all of the above, as most if not all are based on a misunderstanding of what is fundamental to the religion and what is cultural adaptation. Cultural adaptation is not necessarily wrongful. To give a fictitious example, If everybody in a given city or region had the habit of eating cashews at lunchtime on First Tuesdays to pay homage to some kind of "nut deity", there is nothing stopping people from turning Cashews Tuesday into, say, a devotion to St. Bob, bishop and martyr, who dedicated his life to helping nuts and the poor but was slain by a marauding crowd of masonic zealots. Of course masons will chip away (so to speak) trying to spread fear uncertainty and doubt, saying that cashews have some kind of geometric shape that means the whole thing is a masonic symbol of a partial eclipse, and so credit themselves with having invented everything and ridiculing Catholics as somehow worshiping the Sun and Moon. Catholics are then left bemused at this bizarre accusation and it will then take several generations before a defector from the Masons reveals that the whole thing was made up, but century after century people will come up with new ways to attack what by that time has become part of the Catholic liturgical calendar.

The whole sacrifice of the Mass is Christ centered.  

Sorry. I as just venting. It is so difficult to reason with Protestants.

It depends on the protestant sect.  For example, the Lutherans prefer a Crucifix to a cross.

I would also like to add that one of the biggest problems with Protestantism is that their faith teaches the whole "once saved always saved" hoax. That is a very dangerous belief to hold. If you think you're already gauranteed to go to Heaven, then why do penance? Why repent for your sins? Why be nice to people? Why not be greedy? Hey, you're going to Heaven anyway, right? That is what runs through the Protestants' minds, and it is extremely dangerous and heretical.