In the given question, a word has been given and there are three ways in which the word has been used, in similar or different forms. You need to see which of the sentences have correctly used the highlighted word, and mark that as your answer. Incumbency
i. commissary's court at Charleston / suspended him for ceremonial irregularities / to a lay delegate and the / he left his incumbency of Savannah.
ii. I have tried to add to her general information and / to bring her into easy and natural relations with people / incumbency , to enlarge her acquaintance with things around her, and / while not confining myself to any special system of instruction.
iii. randomly changing the lists of places / some locations and adding others / they have visited, possibly by removing / differential incumbency disguises individuals' information by.

1.       (d) 'Incumbency' is a noun and means 'the holding of an office or the period during which one is held'. Sentence i after rearrangement - 'He left his incumbency of Savannah to a lay delegate and the commissary's court at Charleston suspended him for ceremonial irregularities.' In sentence i: Here 'Savannah' is an organisation and 'he leaving his office' makes perfect sense here. Hence, the sentence uses the given word correctly. Sentence ii after rearrangement - 'While not confining myself to any special system of instruction, I have tried to add to her general information and incumbency , to enlarge her acquaintance with things around her, and to bring her into easy and natural relations with people.' In sentence ii: 'Incumbency' does not fit in the context of the sentence as there is no office/designation being talked about here. Sentence iii after rearrangement - 'Differential incumbency disguises individuals' information by randomly changing the lists of places they have visited, possibly by removing some locations and adding others.' In sentence iii: 'Disguising information' (disguise = conceal the nature/existence of something) and 'incumbency' are unrelated ideas and hence the highlighted word is used incorrectly here. 'Privacy' would have been better in place of 'incumbency'. Answer is option (d).