In this question, the author tried to contrast the age laws in his nation and that of other countries. However, we need to be conscious of the application of punctuation and conjunction here.

Option A - Incorrect
'Although' cannot be used to show a contrast between two things. Hence, this claim is not correct.

Option B - Incorrect
The use of semicolon before the dependent clause is wrong (semicolons are to be used before independent clauses), and it lays emphasis on the contract of the number 18 instead of the age laws.

Option C - Incorrect
The conjunction in use doesn't show contrast.

Option D - Incorrect
This claim is not correct because it uses more or less in contrasting the age laws in different countries instead of higher and lower, which is most acceptable in this context.

Option E - Correct
It uses 'but' which is the best conjunction used for contrast. It also uses 'higher' and 'lower', which is the most appropriate terminology to use in the context associated with 'age law' in a nation.