Law @ meetings

Explanation as per the answer and Sentence wise :

sentence 1 : as per section 172 (3) there is no ad-hoc condition that 21 days notice should be given to EACH AND EVERY MEMBER

sentence 2 : the inability of the company to deliver the notice due to technical error or the inability of the member to recieve the notice shall not make the MEETING invalid

sentence 3 : if the opinion of D is accepted then  2 meanings woulld arise - 

                        1. if the notice is not delivered to a particular member then the meeting held would be a VALID ONE

                        2. if the notice is posted in less than 21 days then the meeting would be an INVALID one even if the the Shareholder recieved the notice say before 2 days

The controversy between the above two meanings is what the question is all about. 

OPINION : D's opinion is invalid as the notice was rightly posted 21 days before the meeting and also the company had made a public announcement . Hence the meeting held is a valid one beyond doubt .