Mothers milk

Students in an science class were taking a mid term. The last question was, "Name 7 advantages of Mothers Milk," worth 70 points or none at all. One student could only think of 6 advantages; he struggled to think of the seventh as he wrote the 6:

1. It is perfect formula for the child.
2.. It provides immunity against several diseases.
3. It is always at the right temperature.
4. It is inexpensive.
5. It bonds the child to mother, and vice versa.
6. It is always available as needed.

And then, the student was stuck. Finally, just before the bell indicating
the end of the test rang, he wrote:

7. It comes in such cute containers. He got an "A"