Read the following paragraph and answer the question. Give ONLY the answer, no other words or explanation.

For example:

Answer: <most likely answer, as short as possible>.

Paragraph: I was late for work today because I had a hangover . I have n't had a workday hangover in a million years . But , Rick and I started drinking on our patio early . Alex came over and joined us .

Question: What was the cause of my hangover ?
None of the above choices .
Drinking alcohol.