One of the perennial problems of the tourist industry is "that of fitting what people want to see into the time they have available to see it in."
One of the perennial problems of the tourist industry is "that of fitting what people want to see into the time they have available to see it in." Correct Answer fitting what people want to see into the time they have available
এই বাক্যের subject - এর complement হিসেবে is verb এর পর fit - এর সাথে ing যুক্ত হবে। Option (d) - তে for seeing অতিরিক্ত যোগ করা হয়েছে। তাই সঠিক উত্তর (b)।