When a cat embryo is developing, the embryo produces a unique type of hemoglobin that is not found in the blood of adult cats or kittens. What is best explanation of how the embryo can produce a different type of hemoglobin from adult cats and kittens?

Question 5 options:

Cats lose genes over their lifetime

Cats gain more genes throughout their lifetime

Cats express different genes for different types of hemoglobin at different times in their development

The embryo has different genes from adult cats and kittens