What is the main issue associated with bid shopping?

Bid shopping refers to the practice where general contractors solicit lower bids from subcontractors after the bids have already been submitted. This generally occurs once a contractor has won the bid, and they seek to negotiate the price down by leveraging the subcontractor's original bid against other potential lower offers. The practice is considered unethical because it undermines the trust and integrity of the bidding process. It can lead to diminished profit margins for subcontractors and can result in a negative impact on the quality of work, as subcontractors might cut corners to maintain profitability.

In contrast, the other options present scenarios that either do not accurately reflect the nature of bid shopping or describe legitimate practices. For example, enhancing contractor competition is a positive approach to leveraging bids, while standard pricing guidelines and bid verification processes are meant to standardize and ensure fairness in bidding. None of these capture the essence of the ethics and consequences surrounding bid shopping.