Question

Paul is feeling romantic toward his wife. she is most likely to detect his interest in her by changes in the appearance of his eyes caused by

Answer 1

I believe the answer is: dilation of the pupils

Our pupils would automatically dilated whenever we feel a certain level of excitement. During interaction between two different people, this excitement could be interpreted as sexual attraction. This is why Paul's wife could detect paul's interest. (especially if they are currently conducting a physical contact)

Answer 2

the dilation or the widening of the pupils. The dilation of the pupils is usually an involuntary body movement that would occur if one is excited or aroused by something, which is quite normal for most people to exhibit if they are in love and looking at the person they love.