In writing is not a requirement of a valid contract in the context of revenue recognition. Hence, option d) is correct.
What is Written Contract?
A written contract is a printed document outlining the rights and obligations of the parties. These contracts are written down and contain the signatures of all parties involved, making them legally binding as opposed to oral agreements. The terms of any agreement are often protected by written contracts.
Making an agreement into a written contract has the effect of giving it legal force. When a written contract is signed, it contains detailed information about the agreement, including occasionally details on what actions may be performed or will be taken when an event specified in the contract occurs. A written contract's main function is to lay out the specifics of a business agreement.
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