Select the most appropriate option to substitute the bracketed segment in the given sentence. If there is no need to substitute it, select 'no substitution required'.
It is expected that this police power will only apply to air and (sea routes between the Great Britain and the Northern Ireland).
1
Sea routes across the Great Britain and Northern Ireland
2
Sea routes across the Great Britain and the Northern Ireland
3
Sea routes between Great Britain and Northern Ireland
4
No substitution required