Select the correct Active/Passive form of the given sentence.

Rohan said, “Alright, yes, I made a mistake by investing in Crypto currency.”

Rohan admitted that he had made a mistake by investing in Crypto currency.

The correct active/passive form of the given sentence is Rohan admitted that he had made a mistake by investing in Crypto currency.

The sentence is in the simple past tense, which is used to describe an action that happened in the past. The active voice of the sentence is formed by putting the subject of the sentence before the verb and removing the word "by." In this case, the subject of the sentence is "Rohan" and the verb is "admit." So, the active form of the sentence is "Rohan admitted that he had made a mistake by investing in Crypto currency."

The other options are incorrect because:

• Rohan said that alright and yes he had made a mistake by investing in Crypto currency." This is a combination of the active and passive voice.
• Rohan admitted his mistake and said that he should not have invested in Crypto currency." This is correct, but it is not the most concise form of the sentence.
• Rohan admitted his mistake and said that he had made a mistake by investing in Crypto currency." This is the most concise form of the sentence.