1. Здесь все утверждения подходят.
b) People have never travelled as much as today. Nowadays travelling is very popular. Peopleon our planet can’t live without travelling now. Tourism has become a highly developed business. There are express trains, cars and jet-air liners all of that provide you with comfort and security.
4.
travelling for a purpose - to learn a foreign language, to gain some working experience overseas, to visit business partners, to take part in a research expedition, to visit friends abroadto escape daily routine for a while.
travelling for pleasure - to relax on the beach, to practice hobbies like scuba diving or mountain climbing, to do some sightseeing, to participate in some international cultural events.