A、Because they are busy serving food to their children. B、Because they are busy keeping order at the dinner table. C、Because the

As any homemaker who has tried to keep order at the dinner table knows, there is far more to a family meal than food.(32)Sociologist Michael Lewis has been studying 50 families to find out just how much more. Lewis and his co-workers carried out their study by videotaping the families while they ate ordinary meals in their own homes. They found that parents with small families talk actively with each other and their children.(33)But as the number of children gets larger, conversation gives way to the parents’ efforts to control the loud noise they make. That can have an important effect on the children. "(34)In general, the more question-asking the parents do, the higher the children’s IQ scores are," Lewis says. "And the more children there are, the less question-asking there is."(35)The study also provides an explanation for why middle children often seem to have a harder time in life than their brothers and sisters. Lewis found that in families with three or four children, dinner conversation is likely to center on the oldest child, who has the most to talk about, and the youngest, who needs the most attention.(35)"Middle children are invisible," says Lewis. "When you see someone get up from the table and walk around during dinner, it’s often the case that it’s the middle child." There is, however, one thing that stops all conversation and prevents anyone from having attention: "When the TV is on," Lewis says, "dinner is a non-event. "
32. What is the purpose of writing the passage?
33. Why do parents with large families ask fewer questions at dinner?
34. What can we learn from the research?
35. Which statement would the speaker agree with?