Volume of the cubical container = 20 × 20 × 20 = 8000 cm&sup3; = 8 L.<br><br>
&bull; Water discharged in 5 minutes = 1.2 × 5 = 6 L<br>
&bull; Water left = 8 − 6 = 2 L<br>
&bull; Fraction left = \(\frac{2}{8} = \frac{1}{4}\)<br><br>
Final Answer: B: \(\frac{1}{4}\)