Explanation:
The Froude number is a dimensionless number that characterizes the flow regime of a fluid. It is defined as the ratio of the flow velocity to the velocity of gravity waves in the fluid. The value of the Froude number determines the type of hydraulic jump that occurs in a flow.

A hydraulic jump is a phenomenon that occurs when a high-velocity flow abruptly changes to a lower velocity flow. It is characterized by a sudden rise in water level, turbulence, and energy dissipation. Hydraulic jumps are commonly observed in open-channel flow, such as rivers and spillways.

In this case, the Froude number of the hydraulic jump is given as 5.5. Based on the value of the Froude number, the hydraulic jump can be classified as a steady jump.

Explanation of the options:

a) Undular jump: An undular jump occurs when the Froude number is less than 1. It is characterized by smooth, rolling waves downstream of the jump. Since the given Froude number is 5.5, which is greater than 1, the jump cannot be classified as an undular jump.

b) Oscillating jump: An oscillating jump occurs when the Froude number is between 1 and 1.7. It is characterized by the formation of standing waves downstream of the jump. Since the given Froude number is 5.5, which is greater than 1.7, the jump cannot be classified as an oscillating jump.

c) Weak jump: A weak jump occurs when the Froude number is between 1.7 and 2.5. It is characterized by a small rise in water level and weak turbulence downstream of the jump. Since the given Froude number is 5.5, which is greater than 2.5, the jump cannot be classified as a weak jump.

d) Steady jump: A steady jump occurs when the Froude number is greater than 2.5. It is characterized by a sudden rise in water level, strong turbulence, and energy dissipation downstream of the jump. Since the given Froude number is 5.5, which is greater than 2.5, the jump can be classified as a steady jump.

Therefore, the correct answer is option 'D' - steady jump.