Which one of the following under Indian Evidence Act is not a kind of estoppel?

Regarding the given multiple-choice question, the correct answer is a) Estoppel by will.                                  The Indian Evidence Act, 1872 recognizes different kinds of estoppel which are as follows:   a) Estoppel by deed: This type of estoppel arises when a party has made a solemn assertion in a deed or other instrument in writing, and is precluded from denying the truth of that assertion in a subsequent legal proceeding. b) Estoppel by conduct: This type of estoppel arises when a party has by their conduct, acquiesced to a certain state of affairs or has induced another party to believe in the existence of certain facts. The party is then precluded from denying the existence of those facts in a subsequent legal proceeding. c) Estoppel by record: This type of estoppel arises when a fact has been previously determined by a judicial or quasi-judicial tribunal, and that determination is final and conclusive between the parties to the proceeding. However, "estoppel by will" is not a recognized type of estoppel under the Indian Evidence Act, 1872. "Estoppel by will" is a legal doctrine under English law, which is based on the principle that a person cannot make a representation or promise in their will, and then act in a way that is inconsistent with that representation or promise.