The following shows the monthly sales in units of six salespersons before and after a bonus plan was introduced. At $95\%$ confidence, determine whether the bonus plan has increased sales significantly. $($For the following matched samples, let the difference $"d"$ be: $d=$ after $-$ before.$)$

Monthly Sales

$\backslash$table$[[$Salesperson After,Before,$],[1,94,90],[2,82,84],[3,90,84],[4,76,70],[5,79,80],[6,85,80]]$

If the test statistic for this problem is equal to $2\mathrm{.}05,$ has the bonus plan increased sales?

Select one:

A$.$ Reject null hypothesis, therefore, the bouns plan has not increased sales

B$.$ Reject null hypothesis, therefore, the bouns plan has increased sales

C$.$ Fail to reject null hypothesis, therefore, the bouns plan has not increased sales

D$.$ Fail to reject null hypothesis, therefore, the bouns plan has increased sales