Changing modifier should change the noun preceding ,
On 3 February 2010, “The walking man”, a life size bronze piece sculpted by Swiss Sculptor Alberto Giacometti was auctioned for a record $103.7 million, for the highest price ever paid for a sculpture sold at public auction, beating the record of a 5000-year old anthromorphic lioness sold for $57.2 million in 2007.
Here, There are two modifiers.
first one a life sixe bronze piece, which is talking about "The walking man"
second one highest price, which is a record 103.7 million. THere is no need of for. Hence C is the answer.
(A) Alberto Giacometti was auctioned for a record $103.7 million, for
(B) Alberto Giacometti, which was auctioned for a record $103.7 million, was
who was auctioned? alberto Giacometti?
© Alberto Giacometti, was auctioned for a record $103.7 million,
(D) Alberto Giacometti, auctioned for a record $103.7 million, was
who was auctioned? alberto Giacometti?
(E) Alberto Giacometti, was auctioned for a record $103.7 million, and was