What type of contract is primarily utilized in sealed bidding?

In the context of sealed bidding, the type of contract that is primarily utilized is the Firm-Fixed-Price or Fixed-Price Contracts. These contracts are designed to provide a specific price for a product or service, which is determined at the outset of the contract. This approach is beneficial in sealed bidding scenarios because it allows for a straightforward comparison of bids from different contractors based on a clear, fixed price without the need for further negotiation or uncertainty regarding costs.

Sealed bidding emphasizes competition and transparency, where contractors submit their best offers without knowledge of others' bids, making fixed prices essential for fairness and clarity. A Firm-Fixed-Price contract enables both the government and contractors to have a well-defined scope of work and a predetermined cost, thus reducing the risk for parties involved.

In contrast, the other contract types include elements that introduce unpredictability or variable costs, such as cost reimbursement or time-based billing, which are less suitable for a competitive, sealed bidding environment. This ensures that the correct answer highlights the suitability of Firm-Fixed-Price contracts in this specific contracting scenario.