TOEFL Reading: ETS-TOEFL阅读机经 - F8B_A04I5BM7316BL$

Why does the author mention that the efforts of some woodblock engravers "lent an aura of documentary realism to a magazine's pages?" A. To explain why woodblock engravers believed they could succeed in imitating pictorial elements of photography beyond tonal effects. B. To suggest a reason why such artists were interested in creating tonal effects even though their medium was not well suited for creating tonal effects. C. To suggest a reason why European and American pictorial became so popular in the 1840s and 1850s. D. To explain why illustrators could portray more realistic images than photography could.