problem arises when choosing between option A and D
Second part of both options are almost same
differences are in first part of both of them
in option A,use of "The first states a problem with existing optical lenses" makes it a genralised statement applicable to all types of lenses which is not the actual case
So correct answer option D
Second part of both options are almost same
differences are in first part of both of them
in option A,use of "The first states a problem with existing optical lenses" makes it a genralised statement applicable to all types of lenses which is not the actual case
So correct answer option D
