Concept:The correct fixed phrase is "up for sale".It is used to show that something is offered or available to be purchased.Explanation:The sentence talks about "those properties".When properties are "up for sale", they are placed on the market for buyers.This is a standard English idiom.We cannot say "up on sale", "out for sale", or "down for sale".These words do not form the correct expression.Only "up for" gives the proper meaning of being available to be sold.Therefore, the complete sentence should read: "Those properties are up for sale."We do not need any other preposition after "sale".So the best choice is option A.Answer:A. up for