Step 1: Standard Tatami Dimensions.
\n- Standard Japanese tatami mats are rectangular. \n- Approximate dimensions: length ≈ 1.91 m, width ≈ 0.955 m. \n\n \n
Step 2: Proportion Analysis.
\nCalculating the length-to-width ratio: \n\[\n\text{Ratio} = \frac{1.91}{0.955} \approx 2.0\n\] \nHowever, the intended proportion for tatami mats is based on \(\sqrt{2}\), resulting in a ratio of: \n\[\n\text{Ratio} = 1 : \sqrt{2} \approx 1 : 1.414\n\] \n\n \n
Step 3: Option Verification.
\nOption (A) is the only one that aligns with the traditional tatami ratio. \n\n \n
Final Answer: \n\[\n\boxed{1 : 1.414}\n\]