What will be the suitable answer for this question can anyone please answer???????

Here CH3- will attack below the plane to the carbon where hydrogen is attached due steric crowding at second carbon attack will not take place at that carbon I am posting u a sampl...

check this mechanism

thing to keep in mind is stereochemistry of the epoxide.Consistent with an SN2 reaction, if the reaction occurs at a secondary carbon, we will observe inversion of configuration: