Animal dander would be the answer you're looking for.
Hope this helps :)
Answer:
C
Explanation:
The brother has different alleles for the blood type gene than his sister does. Blood type is inherited from parents like many other traits that can be displayed on a punnet square. Depending on what the parents blood type alleles were, the brother and sister could have different blood types.
A different number of chromosomes doesn't lead to different blood types, so D is wrong. And A is incorrect because the number genes also does not affect blood type. And I think the blood type genes are on the same chromosome, so B is wrong. C is correct because blood type is inherited by alleles, and different alleles can cause different traits, such as blood types.
Mitosis is a type of cell division that results in two daughter cells each having the same number and kind of chromosomes as the parent nucleus, typical of ordinary tissue growth. Mitosis is important because the organism must:
1. replace cells that have worn out or died
2. repair tissue that is damaged
3. add cells in order to grow
4. make new kinds of cells in order to develop
B pimples can last more than 2 days
