Explanation:

Correct answer is (d). There is an error in part D of the sentence. Here the verb ‘wants’ in the part D is wrongly used. It should be replaced by ‘want’ as the subject ‘customers’ is a plural noun. Hence the verb will be replaced by the plural form of the verb.
The correct sentence would be “The new mobile app Yatra Mini, features only the relevant product lines-bus, train, and budget hotels to appeal to customers who have limitations of phone memory space and want to keep data usage to the minimum.” Hence, option D is correct