The most visible instrument that parties use to formulate, convey, and promote public policy is

The most visible instrument that parties use to formulate, convey, and promote public policy is "its platform".

National party platforms refers to an announcement of the general and particular reasoning and approach objectives of a political gathering, normally proclaimed at the national tradition; the most unmistakable instrument that gatherings use to detail, pass on, and advance open strategy. 

It’s obvious the asnwer is false