in the figure shown, which pair of angles must be complementary?

∠aoc and ∠dob

∠cod and ∠dob

∠cob and ∠aoc

∠aoc and ∠cod

B.) ∠COD and ∠DOB

[ It is because, they both lie under the perpendicular so their sum would be equal to 90 degrees, hence, they are complimentary ]

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