Question

how can the man tell how cold it is outside? the water in the creek; thermometer; his spit freezes; his toes are numb

Explanation:

This question refers to Jack London's To Build a Fire. In the story, the man uses the speed at which his spit freezes in the air to gauge the extreme cold (around -75°F/-59°C), as he lacks a thermometer. The other options are incorrect: the creek's state doesn't directly indicate the exact cold, he has no thermometer, and numb toes are a late sign of cold exposure, not a way to measure temperature.

Answer:

C. his spit freezes