A set of numbers has the property that for any number t in the set, t + 1 is in the set. If -1 is in the set, which of the following must also be in the set?
I. 3
II. 1
III. 5
Choose the correct choice from the following
A) I only	B) II only	C) I and II only	D) II and III only	E) I, II, and III
The question is which of the followingmustbe in the set, notcouldbe in the set.   If -1 is in the set so must be   -1+1= 
<gadget id="calculator">  -1+1</gadget>
<output>0</output>
0, as 0 is in the set so must be   0+1= 
<gadget id="calculator">  0+1</gadget>
<output>1</output>
1, as 1 is in the set so must be   1+1= 
<gadget id="calculator">  1+1</gadget>
<output>2</output>
2 and so on. So basically knowing that -1 is in the set we can say that ALL numbers more than -1 are also in the set.   Answer: I, II, and III.
<result>E</result>
A set of numbers has the property that for any number t in the set, t + 1 is in the set. If -1 is in the set, which of the following must also be in the set?
I. 3
II. 1
III. 5