| a | 3 | |||
| 3 | 1 | 4 | ||
| 2 | 5 | 1 | 3 | |
| 1 | 4 | 2 | ||
| b |
\textbf{139.} Consider the Latin square below. Taking the ordered pair $(a, b)$, which is correct?
\medskip
\begin{minipage}{0.35\textwidth}
\begin{tabular}{|c|c|c|c|c|}
\hline
a & 3 & & & \\
\hline
3 & 1 & 4 & & \\
\hline
2 & 5 & 1 & 3 & \\
\hline
1 & 4 & 2 & & \\
\hline
b & & & & \\
\hline
\end{tabular}
\end{minipage}
\hfill
\begin{minipage}{0.55\textwidth}
(1) $(5,3)$\\
(2) $(1,4)$\\
(3) $(2,1)$\\
(4) $(4,1)$
\end{minipage}
\medskip