Final answer:
The correct word pair for the student's sentence based on the provided context is 'stoic' and 'wistful', indicating a father who is generally unemotional but occasionally expresses a longing for the past.
Step-by-step explanation:
The student's question asks for the selection of the appropriate word pair to fill in the sentence based on the context provided. Considering the references given, the correct answer is option 1) stoic...wistful. The term 'stoic' refers to someone who does not show much emotion or reaction to pain or pleasure, which aligns with the description of a father rarely showing his emotions. The term 'wistful' represents having a feeling of vague or regretful longing, indicative of the description of the father becoming reflective and sentimental about the past. From the references provided, we can gauge that a stoic person may have moments of expressive emotion, manifesting as a 'cry-smile' when experiencing strong positive feelings. Thus, most of the time the father maintained a stoic demeanor, but occasionally, he appeared wistful.