The correct way of Gender neutralization  in formal/traditional email writing is*Dear Sir/ MadamRespected Sir/MadamDear SirRespected Sir

In formal or traditional email writing, gender neutralization is important to ensure inclusivity and professionalism. The most appropriate salutation when you do not know the gender of the recipient is "Dear Sir/Madam." This option is widely accepted and recognized as respectful and neutral.

Using "Dear Sir/Madam" addresses both male and female recipients and is suitable for various formal communications. Here’s a breakdown of the options you provided:

1. Dear Sir/Madam - Correct and gender-neutral.
2. Respected Sir/Madam - While polite, it is less standard.
3. Dear Sir - Gender-specific and should be avoided unless the recipient's gender is known.
4. Respected Sir - Also gender-specific and not recommended when addressing unknown recipients.

Therefore, "Dear Sir/Madam" is the best choice for gender neutralization in formal email writing, ensuring that you communicate with respect and professionalism.