prude_sb wrote:
Art historians are using a process known as infrared scanning in analyzing the Mona Lisa to determine if it has been altered since completion and if Leonardo da Vinci first sketched the figure in black, as done by many artists of the time.
(A) if it has been altered since completion and if Leonardo da Vinci first sketched the figure in black, as done
(B) if it had been altered since completion and if Leonardo da Vinci first sketched the figure in black, a practice employed
(C) whether it has been altered since completion and whether Leonardo da Vinci first sketched the figure in black, a practice employed
(D) whether it was altered since completion and whether Leonardo da Vinci first sketched the figure in black, as was done
(E) whether it had been altered since completion and whether Leonardo da Vinci first sketched the figure in black, a practice done
C.
whether - more appropriate. A and B out.
since - implies from past till now - so, "has been" is more appropriate. Only C stands, but I have trouble with the last part (highlighted). What was done by artists of the time - Da Vinci sketching figures in black? Certainly not, but the construction seems to imply that. D is better in this aspect.