Value chain activities are the:

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a$)$ activities or tasks most crucial to implementing the firm's business strategy.

$$ b$)$ activities or tasks the firm completes in order to produce products and then sell, distribute, and service those products in ways that create value for customers.

C$)$ activities or tasks the firm completes to support the work being done to produce, sell, distribute, and service the products the firm is producing.

$$ d$)$ activities or tasks most likely to be imitated by competitors.