Answer:
Correct option: (A)
Explanation:
The correlating linear model to investigate the use of text messaging over time is:

The general simple linear regression line is given by,

Here,
α = intercept of y,
β = slope (or regression) coefficient,
X = independent variable = number of years after 2006
Y = dependent variable = average number of text messages a person sends monthly.
The given regression line (or estimating line) is,
.
The y-intercept is the expected mean value of Y when X = 0.
Compute the y-intercept as follows:


So, the y-intercept of 65 implies that in 2006 the average number of texts sent by a person is 65 texts per month.
Thus, the correct option is (A).