In Many Developing Countries, Children Become Valuable as Factory Workers

In many developing countries, children become valuable as factory workers in middle childhood because of their __________.

A) ability to perform gross motor tasks such threading a needle on a sewing machine
B) cognitive ability to perform complex conceptual tasks such as designing products
C) emotional stability, because some adult factory employees are hot-tempered
D) ability to perform intricate fine motor tasks such as weaving rugs