Correct option is D
The statement mentions that country T has a higher average age than country X, but this does not necessarily mean it has a higher percentage of older people (e.g., "higher average age" could result from fewer children rather than more older people). Thus, I cannot be assumed.
The statement does not provide any information about whether 'Pick2Wear' does not suit youngsters. It only indicates that it failed in country X and may perform better in country T due to a higher average age. There is no explicit link between its failure and youngsters' preferences. Thus, II cannot be assumed.