The correct option is B 24th January, 20XX
The correct format of writing the date (in India and most other countries) is: Day/Month/Year.
Option A follows the Day/Month/Year (24/January/20XX) format. Hence A is the correct option.
Option B is incorrect because the year is not mentioned.
Option C is incorrect because the format is in Month/Day/Year format, which is an American format.
Option D is incorrect because the month is not mentioned in words. In a formal notice, it is preferred that the month is written in word form: January. The month is spelled out, to avoid a confusion between the day and month due to different date formats.