They cannot. Two parents with type O negative blood will produce offspring of type O negative.
No.
at least one of them have negative group.
If both parents are O negative than the child will also be O negative. This is a special case with O negative, the same logic doesn't apply to other blood groups.
yes
O- would be the only possible blood type for the child.
If a child does not have the same blood type as either the father or the mother there is nothing to worry about. It is fairly common for a child to have a blood type that combines the blood types of the parents, such as an AB negative child whose parents had A negative and B negative blood.
yes they can
No.
Yes, O negative
most probably not.
at least one of them have negative group.
it is possible but the child can be a positive
yes.
If both parents have Type B blood the only blood type the child can have is either B or O not looking at whether one of the parents is negative or not.
Yes! Parents have two genes for pos/neg blood type, and only one of them needs to be positive for the parent to have positive blood type. Most positive-blooded people have one positive gene and one negative gene. If both positive parents pass on their negative gene, they can have a child with a negative blood type.
Yes. The geneotype for both parents must be AO+- for the child to be OO--
No, At least one parent would have to be an A (or an AB) for a child to have group A blood.