Answer:
Option D
Explanation:
Area of the field $= 200\times 150=30,000 m^{2}$
Volume of the earth dug out from the plot$=50\times 40\times 7=14000m^{3}$
Let the level of the feild raised by x m
$\therefore , 30,000x=14000 \Rightarrow x=\frac{14000}{30000}=0.47 m$