When making a statistical inference about the mean of a normally distributed population based on a sample drawn from that population, which of the following statements is correct, all else being equal?

Question

The 68% confidence interval is wider than the 90% confidence interval.
The 90% confidence interval is narrower than the 95% confidence interval.
The 90% confidence interval is wider than the 99% confidence interval.
The 99% confidence interval is narrower than the 68% confidence interval.

Answer 1

the wider the interval, the higher the confidence

look at the extreme
... if the sample was the entire population
... you would be 100% confident that the mean matched the population