Regarding a confidence interval (CI) equal to zero (doesn't pass through 1) and p value <0.05:

For RELATIVE RISK or ODDS RATIO: statistical significance = CI does NOT include 1 (null value) AND p<0.05. For ABSOLUTE RISK DIFFERENCE: statistical significance = CI does NOT include 0. A NARROWER (lower range) CI means MORE PRECISION and more certainty about the true effect. A wider CI means less precision. So 'lower range = more significant/precise' (C) is correct. Bigger range means less precision (B wrong). The question states CI doesn't pass through 1 and p<0.05, confirming significance. C is correct.