Answer: the correct answer my friend is a intengers because intengers could be either positive or negative.
Step-by-step explanation: for example -1, -6, -2, -10, 9 etc could be intengers. Irrational numbers could be root 6 pi also. Whole numbers are just 0, 1, 2, 3 etc. Natural numbers are 1,2,3,4,5,6. so hopefully a is the correct answer