Toy makers must often account for choking hazards in the new product development process. For instance, Mattel child$-$tests Barbie dolls by recruiting children to play with model dolls to ensure they are not easily breakable. Broken pieces are a common choking hazard, especially for infants and toddlers $($often the younger relatives of the target child$).$ This type of consumer safety testing usually occurs during the $\_\_\_\_\_\_\_\_\_\_$ stage of the new product development process.

business analysis

new product strategy development

product prototype and test market

product concept testing

idea generation