In a breed of cats, black fur is recessive to calico fur. How is it possible that 2 cats with calico fur produce kittens with black fur?

Question

1Both cat parents are heterozygous and passed on a recessive allele to the kittens.

2One cat parent had the recessive allele and passed it on to the kittens.

3Both cat parents are homozygous for their black fur.

4One cat parent had the dominant allele and passed it on to the kittens.

my awnser is one is it right?

Answer 1

1 is correct because since both parents are heterozygous, then they must have the genotypes Bb and Bb. Their offsprings would be BB Bb Bb and bb. bb means one offspring has black fur.