In the following passage some words have been deleted. Fill in the blanks with the help of the alternatives given. Select the most appropriate option for each blank.
Big Ben is the UK’s most iconic symbol. Since 2017, the Elizabeth Tower and the bell inside have been (1) ______ renovation. The structure is 160 years old and (2) ______ regular maintenance. (3) ______ many years, people had been painting the hands and numbers (4) ______ the clock black, but last Thursday, the workers (5) ______ the clock’s original colour, Prussian Blue!
SubQuestion No: 4
Select the most appropriate option for blank No. 4.

Options

A. to
B. of
C. at
D. for

Answer

B