IMO the answer is A.
Verb of 'sensor' is shuts and 'that' is 'guages'. Here, 'that guages....' modifies 'sensor'. So the question is right as is.
Verb of 'sensor' is shuts and 'that' is 'guages'. Here, 'that guages....' modifies 'sensor'. So the question is right as is.







.jpg)

