The sentence Il fait tres chaud en ___ means "It is very hot in ___." This question tests knowledge of the French seasons and their associated weather.
The correct answer is ete (summer). Summer is the season characterised by the highest temperatures and the most heat. The expression il fait tres chaud (it is very hot) is most naturally associated with summer.
The other seasons do not match:
printemps (spring) is mild and warm, but not typically described as tres chaud
automne (autumn/fall) is cool with falling temperatures
hiver (winter) is the coldest season, the opposite of tres chaud
The four seasons in French are: le printemps (spring), l'ete (summer), l'automne (autumn), and l'hiver (winter). Note that en is the preposition used before ete, automne, and hiver, while au is used before printemps.
