Estoppel can be ........

Indian Evidence Act (IEA) 1872 Estoppel

Estoppel can be:

by matter of record resulting from the judgment of a competent court

by deed resulting from entering into a solemn engagement as to certain facts

by pais arising from agreement or contract and from act or conduct of misrepresentation resulting in a change of position

all the above.

Explanation:

- Option 1: Estoppel by matter of record results from the judgment of a competent court. This means a court decision can prevent re-litigating the same issue.

- Option 2: Estoppel by deed results from entering into a solemn engagement as to certain facts. Essentially, parties cannot deny facts established in legal documents they signed.

- Option 3: Estoppel by pais arises from agreement or contract and from act or conduct of misrepresentation resulting in a change of position. It prevents someone from going back on their word when it causes the other party harm.

- Option 4: All the above. This indicates that estoppel can be by matter of record, deed, or pais.

Your selection of Option 4: all the above is correct, encompassing all forms of estoppel.