Final answer:
The Shaka Triad is an example of international style of early Buddhist art at Horyuji due to its incorporation of architectural features adopted from other cultures during that time period.
Step-by-step explanation:
The Shaka Triad is described as an example of the International style of early Buddhist art at Horyuji because it reflects the influence of international artistic and cultural exchanges in East Asia during that time period.
The International style of early Buddhist art at Horyuji includes rock-cut temples, wooden towers, and huge wooden halls, which were architectural features not previously seen in East Asia. These features were adopted from other cultures, particularly from mainland rulers, and incorporated into the Buddhist art at Horyuji.