Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the questions.

According to some Canadian news media, university students don't like to share their own cultures with each other and are not keen to learn about new ones. However, a study conducted earlier this year at the University of Winnipeg found the opposite.

Its aim was to gauge undergraduate students' attitude towards cultural identity and cultural diversity. It was influenced by the findings of a 2021 study that examined how nine daily Canadian newspapers defined the term multiculturalism'.

The current study included 10 undergraduate students who participated in two discussions about culture and heritage. All participants agreed on the importance of multiculturalism. Seven of them had arrived in Canada in the last 10 years from different places including the Philippines, Pakistan, and Nigeria. The students talked about where they, their parents, and their grandparents came from, discussing everything from language to festivals, religion, and traditions. Three groups of students emerged. The first group maintained a strong connection with their heritage culture and values, and shared stories about their customs and how they made sure they didn't forget their heritage language. For example, one of them still liked listening to music in his home language. The second group felt a sense of belonging to a blend of cultures. They were exposed to different cultures when they grew up, however, they were open to and interested in experiencing other cultures through festivals and friends. The third group had experienced language and culture loss through the process of becoming Canadians. Although they were sad about that loss, they still felt enthusiastic about enriching Canadian culture and making it more diverse.

We had to _____ their invitation to lunch as we had a previous engagement.