Answer:
D)
Step-by-step explanation:
Let the original length be 'x'.
Percentage error = 5 %
So, (100 -5)% = 95% of the original measurement is 3.99 m
   95% of x = 3.99
   [tex]\sf \dfrac{95}{100}*x = 3.99[/tex]
       [tex]\sf x = \dfrac{3.99*100}{95}\\\\x = \dfrac{399}{95}\\\\\\x = 4.2 m[/tex]
Original length = 4.2 m