What type of policy allows for the value of the subject matter to be determined in case of loss?

The correct answer is a valued policy, which specifically allows for the value of the insured subject matter to be predetermined and agreed upon at the start of the policy. This means that in the event of a loss, the insurance payout will be based on the predetermined value stated in the policy, allowing for clarity and agreement on compensation without the need for extensive negotiations or assessments after a loss occurs.

In the context of the provided options, an open policy is not tailored to specify values beforehand, as it may cover various shipments or risks without assigning a specific value to the subject matter. A fixed policy similarly does not apply here, as it typically involves set terms for coverage rather than a predetermined value of loss. A comprehensive policy generally refers to coverage that includes a wide range of risks but does not inherently establish a value for loss compensation.