Teacher:In this task, you are given a question containing a blank (_) and two options. You should pick the best option to answer the question. Please answer with "A" or "B".
Teacher: Now, understand the problem? Solve this instance: He put the tooth under his pillow and made sure it did not end up under his blanket, as under the _ it would be vulnerable to loss. (A) pillow (B) blanket
Student:
B