Using confidence interval concepts, it is found that the incorrect statement is given by:
B. The population proportion is 0.80.
In a sample of n people with a proportion of
, and a confidence level of
, we the <u>confidence interval for the proportion</u> is:
In which z is the z-score that has a p-value of
.
80 developed immunity out of 100, thus, the sample proportion is:

<em>Option A </em>is correct.
The standard error is:

Considering 

Thus,<em> statement E</em> is correct.
<u>90% confidence level,</u> thus the critical value is the value of z that has a p-value of
, so
, which means that <em>statement D</em> is correct.
The margin of error is:

Thus, <em>statement C</em> is correct, which leaves B as the false statement, as we have the sample proportion, and we can only estimate, not guarantee the population proportion.
A similar problem is gien at brainly.com/question/16807970