Final answer:
The detail that indicates trouble at the Cord family farm is the mention of delayed repairs, hinting at financial struggles.
Step-by-step explanation:
The evidence in the text that supports the inference that the Cord family farm is in trouble is option d: "...we could make the repairs we’ve been puttin’ off."
This line suggests that the family has been unable to afford necessary repairs for their property, indicating financial issues and potential farm troubles. Moreover, when combined with the melancholy mood and the hesitation to build better living conditions in lieu of another barn, it further suggests that the farm's resources are stretched, and priorities are being made not out of growth but out of necessity.