Continent ContinentPopRank CountryName IndependenceYear

Asia $2$ India $1947$

Asia $11$ Myanmar $1948$

Europe $34$ Malta NULL

Africa $6$ Algeria NULL

NAmerica $2$ Mexico NULL

CountryBased on the data in the Country table, select the properties satisfied by the composite column $($Continent$,$ ContinentPopRank$).$

Can $($Continent$,$ ContinentPopRank$)$ be a primary key of the Country table?