Experimental design is generally strong against selection-history threats

What can a child in the concrete operational stage do that a child in the preoperational stage cannot?

What will be an ideal response?

Banks and Barber (1971) presented subjects with a matrix of letters where each row was of a different color and then cued with color to indicate which row the subjects should report. They found:

A. That subjects rarely reported the row that was in the complementary color, suggesting that iconic memory is not like an afterimage. B. That subjects commonly reported the row that was in the complementary color, suggesting that iconic memory is like an afterimage. C. That color was not as effective a cue as the tones that were used in the original Sperling studies. D. That subjects tended to report both the required row and the row that was in the complmentary color, suggesting that iconic memory has some of the properties of an afterimage.