A merchant brings a claim for professional negligence against a firm of solicitors which represented the merchant In a breach of contract claim. The claim alleges that the firm did not contact two important witnesses despite the merchant providing the firm detail regarding the witnesses. The court has made an order for standard disclosure.Which of the following statements most accurately describes the parties' obligations regarding documents that must be disclosed?
选项：

A:The parties need only disclose documents upon which they will rely and documents that affect their case adversely or support the other party's case that are or were in their possession.
B:The parties need only disclose documents and evidence which they plan to tender in support of their claim which are or were within their control.
C:The parties need only disclose documents upon which they will rely or documents which adversely affect their case or another party's case or which support another party's case which are or were within their control.
D:The parties need only disclose documents and evidence which supports their case which are or were within their control.
E:The parties need only disclose documents and evidence which supports their case and which are or were within their possession.