In regression analysis, the F-distributed test statistic is used to test the null hypothesis that the slope of the regression line (denoted as $b$) is zero, against the alternative hypothesis that at least one slope is not zero. For a simple linear regression, this simplifies to:

• Null Hypothesis (H₀): $b = 0$
• Alternative Hypothesis (Hₐ): $b \neq 0$

Option A is correct because it accurately reflects the null hypothesis being tested. Options B and C are incorrect as they misinterpret the focus of the F-test, which is on the slope, not the intercept, and the null hypothesis specifically tests for a zero slope.