If a 95% Confidence Interval for the prevalence of cancer smokers aged > 65 years is 56% to 76%, the chance that the prevalence could be less than 56% is -

In this question: 56 to 76 confidence interval covers 95% (2SD) of values. That means 5% of values will fall outside the range of 56-76 → 2.5% values will be below 56 and 2.5% values will be above 76.