I really dont consider gambling or betting of any form to be a source of money.
It is not. But since there is the possibility of the gambler making money, hence the idea that people can make money from it. It is possible under certain circumstance like you know the bookmaker closely, they may be able to give you some tips.
Of the 5, it's parlay that betting type that makes me earn the most. It makes me have better control of my wins and losses because multiple bets on multiple matches are covered.
Parlay should not be in this list. When you make a list you are essentially comparing things that have a similarity Casinos allow parlay because it increases the risk of the loss and the reward for winning. Statistically speaking the casinos make money from the increased frequency of parlay so they allow it, otherwise they would not have offered it.
Dont easily believed on when there are gamblers who do say or claim on making with parlays specially on longer lines. 3 games might be considerable but
above that it seems hard to believe on.
Regarding on the question on what betting type do make money when i do gamble out then its always on money line.