1. The problem asks to represent the statement "he is unhealthy only if he is dirty" using logical statements involving $p$ and $q$.
2. Given:
- $p$: He is healthy
- $q$: He is neat
3. "He is unhealthy" is the negation of $p$, so it is $\neg p$.
4. "He is dirty" is the negation of $q$, so it is $\neg q$.
5. The phrase "only if" means implication: "A only if B" translates to $A \Rightarrow B$.
6. Therefore, "he is unhealthy only if he is dirty" translates to:
$$\neg p \Rightarrow \neg q$$
7. Looking at the options:
- A. $\neg p \Rightarrow \neg q$ (matches our expression)
- B. $\neg p \Rightarrow q$
- C. $p \Rightarrow \neg q$
- D. $\neg q \Rightarrow \neg p$
8. The correct representation is option A.
**Final answer:** A. $\neg p \Rightarrow \neg q$
Logical Implication 3A2Ed1
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