There are 46 countries to get in all. Hong Kong is not counted as it is not a country in its own right. By Very High, it means that the HDI is over 0.8 out of a possible 1. For those who are interested, Hong Kong scores 0.906, putting it at a joint 13th. (Source: List of Countries by HDI Rank).
Data may have changed since this quiz was created. In fact, it probably has.