Bias

When people are faced with a wide range of possibilities they tend to get more lost. You give them 10 multiple choice answers instead of 4 and you just spread the distribution of wrong answers and decrease the number of correct ones. 

When IQ tests were first developed in the early 20th century, they found that people who scored well in math for example also scored higher in other subjects (with some margin left open for variability in each person). This is how intelligence quotient was developed because some people routinely scored higher than others over the same range of subjects. 

IQ isn't everything because even if it predicts the likelihood of higher reasoning it doesn't guarantee the person will choose the wise and empathetic solution. You could be a narcissist ship's captain and let others die before you do because wisdom and altruism are more than just about critical thinking. 

There were test results shown in a survey regarding the efficacy of skin cream to treat rashes where failure to consider the sample size and thinking proportionately would have you give the wrong answer. Those who used no cream had a higher proportion of being cured than those who used the cream but the sample group who used it was considerably higher which fooled many people who only looked at the highest number on the results grid. 

When the survey took into account political leanings of those who took the test the results were similar regardless of affiliation. 

The test was then changed to be about the use of guns versus restriction on them and unsurpsingly those who leaned right politically gave different answers than those who leaned liberal. The reason is of course bias. 

Therefore when we deal with people who have pre-baked bias plus low critical thinking skills we are facing an uphill battle which is something we can anecdotally understand from our life experience.