Correct option is C
To decode the word 'study', we compare the two given sentences. The word ‘study’ appears in both sentences. The code ‘cy’ is the only common code in both, so it must represent the word ‘study’. The other codes differ in both lines, indicating they stand for different words.
Explanation of options: (a) ✘ 'km' appears only in the sentence "study the case" and is not common in both, hence cannot represent 'study'. (b) ✘ 'sp' is used only in the sentence "time to study", and not present in the second sentence, so it likely represents 'time' or 'to'. (c) ✔ 'cy' appears in both sentences and is the only common code, just like the word 'study', making it the correct match. (d) ✘ 'mh' also appears only in one sentence, indicating it is related to another word like 'time' or 'to', not 'study'.