In reality demand and prices are

$$ a$.$ highly certain and not likely to fluctuate during the life of any supply chain decision.

$$ b$.$

highly certain and likely to fluctuate during the life of any supply chain decision.

O c: highly uncertain and not likely to fluctuate during the life

of any supply chain decision.

$$ d$.$ highly uncertain and likely to fluctuate during the life of any supply chain decision.