The（） only allows for adjustment of temperature in each room

Each man and woman must sign ______ full names before entering the examination room.

A.his

B.her
C.their

D.one’s

At the University of Kansas art museum,scientists tested the effect of different colored walls on two groups of visitors to an exhibit of paintings.For the first group the room was painted white;for the second,dark brown.Movement of each group was followed by an electrical equipment under the carpet.The experiment showed that those who entered the dark brown walked more quickly,covered more area,and spent less time in the room than people in the white one.Dark brown made people more active,but the activity ended sooner.Not only the choice of colors but also the general appearance of a room affects those inside.Another experiment presented people with photographs of faces whose energy was to be commented.Three groups of people were used;each was shown the same photos,but each group was in an ordinary room—a nice office.The third was in a tastefully designed living room with carpeting.Results showed that the people in the beautiful room tend to give higher marks to the faces than those in the ugly room did.Other studies that students do better on tests taken in comfortable room than in ordinary-looking or ugly rooms.
Which of the following is the best expression of the main idea of this passage

A.People in beautiful rooms tend to give higher marks to photos of faces than people in ugly rooms
B.The color and general appearance of a room have a deeper effect on the behavior of the people in it
C.The University of Kansas has studied the effects of the color of room on people’s behavior
D.Beautifully furnished,light-coloured rooms make people more comfortable than ugly,dark rooms