In a certain code, 'APPLE' is written as 'EPPLE'. How will 'MANGO' be written in that same code?

In this pattern, only the first letter is replaced by the next vowel (A -> E). Following this, M remains M as it's a consonant, but if the logic is first letter + 4 positions: M+4 = Q. If the logic is only vowels change: A->E, so MENGO.