The correct choice is Option 3: 'Because they can talk to various people, and the teacher is kind.' The passage states: '先生はとても親切で...分かりやすく教えてくれます' (The teacher is very kind and teaches in an easy-to-understand way) and 'いろいろな人と話すのも楽しいです' (Talking to various people is also fun). These reasons match Option 3 perfectly. Analysis of incorrect choices: Option 1 is wrong because the teacher is 'kind' ('親切'), not 'strict' ('厳しい'). Option 2 is wrong because they attend the class on Wednesday nights after work, not meeting their family. Option 4 is not listed as a reason why the class is enjoyable.