*All rEFErEnCEs to homEs in thE DAtA AnD tEst quEstions shoulD BE intErprEtED As onE—FAmily homEs．
notE：grAphs DrAwn to sCAlE．
in 1977 thE numBEr oF Existing homEs solD wAs ApproximAtEly how mAny timEs thE numBEr oF nEw homEs solD
A、3
B、3.5
C、4.5
D、5.5
E、6