Examine the validity of the following concerning the relevant provisions of the Companies Act, 2013:
(i) The Board of Directors of a company refuses to convene the extraordinary general meeting of the members on the ground that the requisitionists have not given an explanatory statement for the resolution proposed to be passed at the meeting.
(ii) The Board of Directors refuses to convene the extraordinary general meeting on the ground that the requisitions have not been signed by the joint holder of the shares.
(iii) Adjournment of the extraordinary general meeting called upon the requisition of members on the ground that the quorum was not present in the meeting.