Please proofread my thesis =D

Dear Experts,

      Hi, I have been wondering whether to use my first thesis format or my second thesis format in making my thesis statement for:

Argumentative essay - What do you think the legal drinking age in your province should be? Give examples (be specific)!

My first format:

In my opinion, the legal drinking age should be 21 years old because by the age of 21: an individual has reached adulthood; an individual has acquired a lot of life experience to aid them in making the right decision; and above all, an individual has been thoroughly educated about the risks of drinking.

Thank you Mister Micawber,

Thats a great thesis, thanks again! However, I have one question regarding your thesis.

In my opinion, the legal drinking age in my province should be 21.  By that age, young people have reached adulthood, have acquired a lot of life experience to aid them in making the right decisions, and have been thoroughly educated about the risks of drinking.

Isnt that faulty reference? should I do:

In my opinion, the legal drinking age in my province should be 21.  By the age of 21, young people have reached adulthood, have acquired a lot of life experience to aid them in making the right decisions, and have been thoroughly educated about the risks of drinking.

Thanks a lot,

Kaito