Name the sets of numbers to which -7/9 belongs

Ok
the sets are
natural numbers (or counting numbers), this is like 1,2,3,4,5 etc

whole numbers, this is including 0, so 0,1,2,3,4,5,6 etc

integers, this includes the previoius set and negatives, so -3,-2,-1,0,1,2,3,4,5 etc

rational numbers, this is the set of numbers that can be written in form a/b where b≠0, so all integers can be written like this, like example -3=-3/1, so -7/9 belongs here

-7/9 goes in the rational set

All i know is thay part a is 48