We perform a statistical test to examine if the mean lifetime of lab mice increases when givenvitamin B12compared to a placebo. Which of the following is a Type I error?

1. Conclude that VitaminB12 increases the mean lifetime when in fact it does.
2. Conclude that VitaminB12 does not increase the mean lifetime when in fact it does not.
3. Conclude that VitaminB12 increases the mean lifetime when in fact it does.
4. Conclude that VitaminB12 increases the mean lifetime when in fact it does not.