When asked to list four advantages of breast milk, the student began to compose whatever came into his head and hoped for the best:

1. No need to boil.

2. Never goes sour.

3. Available whenever necessary.

So far so good – maybe – but there had to be a fourth advantage of breast milk.

So, what is it? He sighed. He frowned. He scowled.

Suddenly, an answer came to him. Clutching his pen, he triumphantly scribbled his definitive answer:

4. Available in attractive containers of varying shapes and sizes.

He received an A.