On a map of England and Wales the distance between St Ives in Cornwall and St Ives in Cambridgeshire measures $$18\text{cm}$$. In reality the distance between the two towns is about $$450\text{km}$$.  Which of the options below is the scale of the map? 
选项为:A:$$1:2500000$$  B:$$1:1000000$$  C:$$1:750000$$  D:$$1:500000$$  E:$$1:250000$$  请回答其中一个选项.