Answer:
A.  .
.
Step-by-step explanation:
We are given that,
x = Number of days where 1 = Sun of 1st week and 7 = Sat of first week.
The corresponding table for the data is given by,
Days        Day Number               Number of Customers
Sun                    1                                     115
Mon                   2                                     77
Tue                    3                                     60
Wed                   4                                     51
Thur                   5                                     68
Fri                      6                                      86
Sat                     7                                      120
The general form of the regression model is  .
.
Using the sinusoidal regression calculator, we get that,
a = 33.690
b = 0.887
c = 1.337
d = 81.684
That is, the sine regression model is  .
.
Thus, option A is the sine regression model for the given data.