A variable wind direction and a speed of 4 knots would be coded as?

The coding for wind direction and speed in meteorological reports follows specific rules for clarity and standardization. A variable wind direction indicates that the wind is changing frequently or is not consistent from any single direction. This is denoted using the abbreviation "VRB," which stands for "Variable."

In the correct code, "VRB04KT," the "VRB" signifies the variability of the wind direction, while "04KT" specifies the wind speed of 4 knots. This concise code effectively communicates to aviation personnel the nature of the wind conditions, allowing for proper flight planning and operational decisions.

The other codes provided in the choices do not appropriately represent a variable wind condition. For example, a code of "00004KT" would imply a calm wind condition with no directional significance, "99904KT" typically indicates winds of 99 knots or more (which is not applicable in this scenario), and "/04KT" does not conform to established meteorological coding standards for indicating wind direction and speed.