One of my friends , whom I ' ve known for years , has a baby son . Recently he said the phrase " They grow up so fast ... " to me . I felt so old at the time .
Why is the narrator 's friend so proud ?
Pick the best answer from the following options:
- They are very wealthy .
 - None of the above choices .
 - They are growing up fast .
 - They are very fast .


None of the above choices .