Final answer:
The sentence given has a grammatical error in the usage of the word 'who'. The correct word should be 'that', which refers to people or things in a restrictive clause. Therefore, the sentence should read: 'The watchman has been keeping the coastline free of raiders that try to sneak ashore in search of gold.' Ans is d) who.
Step-by-step explanation:
The part of the sentence that requires correction is option d) who. The correct connector in this context should be 'that', not 'who'. 'Who' is used to refer to people, while 'that' can refer to people or things in a restrictive clause. Thus, the sentence should read: 'The watchman has been keeping the coastline free of raiders that try to sneak ashore in search of gold.'
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