Seasonal patterns A. cannot be predicted. B. are multiyear runs of observations above or below the trend line. C. reflect a shift in the time series over time. D. are regular repeated patterns.

The correct answer is letter "D": are regular repeated patterns.

Explanation:

In statistics, seasonal patterns are a group of components that tend to repeat their behavior over specific intervals. Those intervals are likely to be one year. Seasonal patterns oppose to cyclical patterns because the latter identifies repeated behavior over intervals that sometimes can be long or some times short.