Based on the data collected in Question 1, the manager of the real estate company claimed that the average selling price of houses is higher than 210 thousands of dollars. At the 5% level of significance, which of the following statements is true?

A.The manager's claim is believable at 5% level

B.The manager's claim is not believable at 5% level

C.The manager's claim is only believable at 10% level

D.The manager's claim is only believable at 1% level