The offer for buy back shall remain open for a period of
A. Not less than 10 days and not exceeding 20 days from the date of despatch of the letter of offer
B. Not less than 15 days and not exceeding 20 days from the date of despatch of the letter of offer
C. Not less than 15 days and not exceeding 30 days from the date of despatch of the letter of offer
D. Not less than 20 days and not exceeding 30 days from the date of despatch of the letter of offer