The main data in the passage is that children who avoid eye contact while answering a question are more likely to come up with the right answer. Option (d) states that by maintaining eye contact a child begins to process information, or cues from the facial expressions, which can distract the child from thinking about the question. Option (a) and (c) bring in a new element to the data. Option (b) weakens the data.

Hence, the correct answer is Option d.