Because of the inequality of bargaining power, the element of voluntary participation without duress may be deemed to be absent in which type of contract?

unconscionable contract/ unenforceable contract

Explanation:

Unconscionable contracts are contracts that is unfair to one party and therefore unenforceable under law, they are considered unjust because it is so one-sided to a party in the contract.

It is a type of contract that leaves one party with no real, meaningful choice, usually due to major differences in bargaining power between the parties.

In a lawsuit, if the court finds a contract to be unconscionable, they will typically declare the contract to be void.

Inequality of bargaining power in law, economics and social sciences refers to a situation where one party to a "bargain", contract or agreement, has more and better alternatives than the other party.

Inequality of bargaining power is generally thought to undermine the freedom of contract, resulting in a disproportionate level of freedom between parties.