Final answer:
The theme in 'Those Winter Sundays' is the relationship between a child and their parent.
Step-by-step explanation:
The theme that the poet develops through word choice in 'Those Winter Sundays' is the relationship between a child and their parent. The poet uses specific words to convey a sense of coldness and distance in the relationship, such as 'cold,' 'frozen,' and 'coldness.' These word choices not only describe the physical temperature of the winter Sundays, but also symbolize the emotional distance between the speaker and their father.