Any two humans on earth, provided one is male and one is female, can marry, or mate, to create a child. Blood type does not affect fertility.
Yes, the O plus boy can marry an O negative girl though there will be a high risk of miscarriage.
of course.
Yes
Any blood type can marry any other blood type.
Yes, blood types do not affect marriage - all blood types can marry each other.
If a 32-year old male is in the AB plus blood group, he can marry a 35-year old female that is in the O blood group without having any problems in pregnancy.
The blood type of your partner has nothing to do with you. Any blood type can be with any other.
o+o+o = o
why not...
you can marry anyone you want
you can marry anyone you want
yes