Answer: The clause is unconscionable
Explanation:An unconscionable clause could be explained as a proposed agreement between two parties such that the terms of agreement is so biased or one-sided and hence unenforceable. The exculpatory clause in the other hand refers to a clause which relieves a party of liability during contract execution.
Based on the facts derived from the context above, Arts' claim that the exculpatory clause in the contract was unconscionable is true, this is because The yellow pages served as Arts' flower's only advertising channel for over twenty years, this is a clear exercise of monopoly. And yellow page negligence cost Arts' flower dearly even after monopolizing their advertisement option and as such yellow pages should be held accountable for negligence.