The sentence contrasts two opposite weather conditions. The word "hot" is already given, so we need its antonym.
a) Cold – Opposite of hot, making the sentence meaningful, so correct ✅.
b) Warm – Similar to hot, not an antonym, so incorrect.
c) Mild – Means moderate, not a direct opposite of hot, so incorrect.
d) Hot – Same as the given word, so incorrect.
Thus, the correct sentence is:
"The weather was extremely hot, but after the storm, it turned cold." ✅
