Marshall takes his 1-year-old son, Marcus, out for a walk. Marcus reaches over to touch a red flower and is stung by a bumblebee sitting on the petals. The next day, Marcus' mother brings home some red flowers. She removes a flower from the arrangement and takes it over for her baby to smell. Marcus cries loudly as soon as he sees it. According to the principles of classical conditioning, what is the conditioned stimulus in this example

The condtioned stimulus is the red flowers.

Explanation:

In classical conditining, a conditioned stimulus (the flowers) is associated with an unrelated consequence, called unconditioned stimulus (the sting). This produces a reaction known as conditioned response (fear).

It's important to acknowledge that any neutral stimulus can become conditioned. In this example, Marshall could have been afraid of yellow flowers, instead of red, if the incident had involved the former.