In the following proof, which justification is correct for line 3? $\begin{array}{llcc}
\text { (1) $ \sim \mathrm{Ba} $ } & & \text { Premise} \
\text { (2) $ (x)(\mathrm{C} x \vee \mathrm{B} x) $ }&/ \mathrm{Ca} & \text {Premise/Conclusion }\
\text{ (3) $ \mathrm{Ca} \vee \mathrm{Ba} $ }&\
\end{array}$

Question

In the following proof, which justification is correct for line 3? $\begin{array}{llcc}
  \text { (1) $ \sim \mathrm{Ba} $ } & & \text {  Premise}  \
 \text { (2) $ (x)(\mathrm{C} x \vee \mathrm{B} x) $ }&/ \mathrm{Ca} &  \text {Premise/Conclusion  }\
 \text{ (3) $ \mathrm{Ca} \vee \mathrm{Ba} $ }&\
\end{array}$

Quizplus · Accepted Answer

The justification for line 3 is Universal Instantiation (UI) applied to line 2, which allows us to infer that the statement holds for a specific instance, in this case, 'a'.

In the Following Proof, Which Justification Is Correct for Line