Rational formula is only applicable to the catchment, which has an area -

Correct option is A

· Rational Formula Application:
· The rational formula is typically used to estimate the peak runoff rate for small catchments with an area of less than 50 km².
· It is not suitable for large catchments because it does not account for factors like storage, infiltration, and complex flow paths.
· Formula: Q=CiA Where:
· Q: Peak runoff
· C: Runoff coefficient
· i: Rainfall intensity
· A: Catchment area