Answer:
B. Antibodies react specifically with an antigen.
Explanation:
Serological tests are blood tests that look for antibodies in your blood. They can involve a number of laboratory techniques. Flucculation tests are based on the precipitation that takes place when antibody and specially prepared antigens are mixed together
Option D centrioles helps cells to divide.
Answer: A dichotomous key is a tool that allows the user to determine the identity of items in the natural world, such as trees, wildflowers, mammals, reptiles, rocks, and fish. Keys consist of a series of choices that lead the user to the correct name of a given item.
Explanation: google