Assertion A: Depth and width required at the entrance to a harbour are more than those required in the channel.Reason R: The entrance to a harbour is usually more exposed to waves as compared to the harbour itself.Select your answer based on the coding system given below:

Docks are for loading, unloading, and repair of ships, while harbours provide safe shelter and anchorage for ships and allow the transfer of passengers and cargo between the ship and the land.