SC's Question number - 953, 954

953). Although no proof yet exists of electromagnetic fields generated by household appliances posing any health threat , mounting scientific evidence has convinced many experts that there is cause for concern.

(A) of electromagnetic fields generated by household appliances posing any health threat

(B) of electromagnetic fields generated by household appliances that pose any threat to health

(C) that electromagnetic fields generated by household appliances pose any threat to health

(D) that poses any threat to health from electromagnetic fields generated by household appliances

(E) for any health threat posed by electromagnetic fields generated by household appliances

954). 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



Answers --

953). OA - C
C can be reconstructed as follows : Although no proof that electromagnetic fields generated by household appliances pose any threat to health yet exists, mounting scientifc evidence has convinced many experts that there is cause for concern.
Restrictive Clause : that electromagnetic fields generated by household appliances pose any threat to health (modifying proof)

A, B - incorrect - "proof of electromagnetic fields" - wrong.

D - incorrect - Proof poses any threat -- wrong

E - incorrect - Passive

954). OA - C - since ---- implies from past till present (now) - so, "has been" is correct

A, B - incorrect - use of "if" - (on GMAT generally whether is preferred over if)

D - incorrect - wrong tense was - must be present tense.

E - incorrect - past perfect (wrong tense) -- illogically suggests alteration was done before the completion of painting