Answer:
how huge the empire was.
Explanation:
The phrase 'the empire on which the sun never sets' was first coined by Fray Francisco de Ugalde. Later, this phrase was used to express how huge and vast the British empire was. British empire had it's territory in most part of the world such as Asia, Europe, America, and Africa.
This phrase meaant that an empire had some parts of it's territory all over the world that some of it is always under the sunlight.
Therefore,the given quote indicates that British empire was huge. Thus option A is correct.