Select the most appropriate option to fill in blank number 4.
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. at.
The preposition "at" is used to indicate a specific point or level, in this case, the temperature at which the camel starts to sweat.
The other prepositions ("in," "with," "for") do not fit the intended meaning of the sentence.
"At" correctly conveys the point at which sweating begins.