The given figures depict the country-wise and age-wise distribution of the people who visit China for business setup.

If in a given year, 500,000 people visited China, then the ratio of the number of Americans with the age group between 20 and 40 years to the Russians with the age group below 20 years who visited China is:

A

4 : 1

B

1 : 2

C

2 : 1

D

1 : 4