Grammar 問題.....

請問two types of .....of後面跟戈個名詞洗唔洗加S丫? 點解我見到有d要有d唔洗ge
As snakewongcm's answer is A okay, I just want to add that there are some exceptions, just happened to be like Two types of ...
Uncountable nouns like: people, food etc shouldn't add s, but as you wrote: two types of peoples, thus, people became countable noun so we should add s as above.

if the noun is countable, we add " s" after the noun.
e.g. cars.
if the noun is uncountable, we do not add "s" after the noun.
e.g. money.