Which of the Following Statements About Language Production Is Correct

Which of the following statements about language production is correct?

A) Roughly the same amount of research has been conducted on language comprehension and language production.
B) It is easier to conduct research on language comprehension than on language production.
C) During the past decade, psychologists have grown even less interested in language production than in previous years.
D) There is much more research on written language production than on spoken language production.