Hair metal and heavy metal were big in the 80s. Many rock'n roll bands were still arising and the many male singers with long hair were receiving praises. Girls wanted them, guys wanted to be them. Many bands repeating this style surfaced in the 80s showing some variations (Bon Jovi, Guns and Roses, and others) and they would appear in movies as well (Rock'n Roll Nightmare, HardRock Zombies, and many others). American movies and culture reach far beyond the States. With music and movies going to other countries, those tendencies would repeat themselves in other countries. To the point of even creating very influential bands. In Japan, during the 80s, thanks to that "imported culture", we have X-Japan, the most notorious rock'n roll band in Japan to this day. The band uses a lot of hard rock, metal, hair metal and punk rock elements on its songs.
The different types of rock music have been popularised by the American film and music industry during the 1980's to a point that it spread out throughout the world. The trend was attracted internationally because of the high American standards of music incorporating the most advanced technologies.
The answer is B. The smaller German nations in the south were afraid that they would easily get beaten by France because at the time, it was known as the strongest land power.
