Elliot Is Led to a Room with Nine Other People

Elliot is led to a room with nine other people. All ten people are then shown a picture of two lines. The line on the left is clearly shorter than the line on the right. But, when the experimenter asks everyone which line is shorter, all of the other people say that the line on the right is shorter. When it is Elliot's turn to respond we would expect him to say that

A) he is not sure which line is shorter
B) the lines are the same length
C) the line on the left is shorter
D) the line on the right is shorter