Final answer:
The number of employees is decreasing by 10% every year.
Step-by-step explanation:
The given function is f(t) = 1.5(0.90)t, where t represents the number of years since the company revised the benefits package.
The base of the exponential function, 0.90, is less than 1, which indicates decay or decrease over time. In this case, the number of employees is decreasing.
The base, 0.90, represents a decrease of 10% each year. So, the correct statement is C) The number of employees is decreasing by 10% every year.