Answer:
p ↔ q
Step-by-step explanation:
Given :
Let p: The integer has one digit.
Let q: The integer is less than 10.
To Find:Which represents "The integer has one digit if and only if the integer is less than 10”?
Solution:
1. p ∧ q denotes “p and q”
2.p ∨ q denotes “p or q" (or both)
3.p → q denotes “if p then q”
4. Biconditional p ↔ q denotes “p if and only if q"
Thus Biconditional p ↔ q represents "The integer has one digit if and only if the integer is less than 10”
Hence Option D is correct p ↔ q