For predicting the straight-line trend in the sales of washing machines (in thousands) on the basis of 8 consecutive years' data, the company calculates 4-year moving averages. If the sales of washing machines for respective years are \( a, b, c, d, e, f, g, \) and \( h \), then which of the following averages will be computed?
(A) \( \frac{a + b + c + d}{4} \)
(B) \( \frac{a + c + d + e}{4} \)
(C) \( \frac{c + d + f + h}{4} \)
(D) \( \frac{b + c + d + e}{4} \)
Choose the correct answer from the options given below: