He did not know the answer and I did not neither.
He did not know the answer and I did not neither. Correct Answer and neither did I
Negative agreement (I did not know the answer) এর ক্ষেত্রে and + either + auxiliary verb negative form + subject অথবা and + neither + auxiliary verb + subject হয়।অপশন (a) তে either এর পর auxiliary verb এর negative form (didn't) না থাকায় তা সঠিক নয়। সঠিক from হলো and neither did I.