What toga was typically worn by boys in ancient Rome?

The toga typically worn by boys in ancient Rome is the toga praetexta. This garment was characterized by its purple border and was worn by young boys before they reached adulthood, signaling their status as freeborn citizens. The toga praetexta was also worn by magistrates and certain priests, which highlights its significance in Roman society.

As boys transitioned into adulthood, they would then wear the toga virilis, a plain white toga signifying their full citizenship and maturity. In contrast, the toga candida was an additional type often worn by candidates in elections, while the toga pulla was worn during periods of mourning. The toga praetexta marked a distinct phase in a boy's life, making it the correct answer for this question.