“回头见(huítóujiàn)” is a common greeting in Chinese. “回头(huítóu)” means to turn one’s head or turn round. And “见(jiàn)” means to see or catch sight of something. However, “回头见(huítóujiàn)” doesn’t mean to turn around and see something. Actually, when someone says “回头见(huítóujiàn)”, he or she intends to say goodbye. This greeting is equivalent to “see you” and “see you next time”. So as for Quiz 1, Mark means to say goodbye to LingLing. And in Quiz 2, A and B both mean “see you,” while C means “you are welcome”, so C is not an appropriate answer.
Nǐmen jìxù wán ba, wǒ xiān zǒu le, huítóujiàn.
你们 继续 玩 吧，我 先 走 了，回头见。
You guys go ahead and continue, I have to go. See you.
Xièxiè nǐde yāoqǐng, huítóujiàn.
谢谢 你的 邀请， 回头见。
Thank you for your invitation, see you next time.
Wǒ qù mǎi diǎn shuǐguǒ, huítóujiàn.
我 去 买 点 水果， 回头见。
I want to go get some fruits, see you.