I asked Beth to give Laura a quick call to ask her if she could come down right away . " She 's coming , " Beth said after the call . Two Chinese students , Toby and Leon ( their American names ) , who both looked about 19 years old , had arrived by now . I could tell that they were excited to accompany us to Dr. Zhang 's home , but they seemed nervous .

Question: Why did the speaker think that the Asian students looked particularly young ?
Answer: The students are smaller in stature and have smooth skin which makes them look youngerNone of the above choices .The speaker is notoriously bad at guessing the age of a person and this is one of those casesThey are actually that young and have skipped some grade levels due to academic activity