Which of the following is the approximate ratio of length to breadth of any standard Engineering drawing sheet?

Correct option is C

According to the Bureau of Indian Standard(BIS) for a drawing sheet the ratio of length to breadth should be 1: √2
Different length and breadth of different type of sheet are given as follows:
Designation               Dimension (Length x Breadth)
A₀                                   841 x 1189
A₁                                     594 x 841       
A₂                                     420 x 594
A₃                                      297 x 420
A₄                                       210 x 297