If heredity is an important determinant of a specific behaviour, what prediction can we make about expression of the behaviour in identical twins reared apart compared to its expression in fraternal twins reared apart?

Fraternal twins will express the behaviour more similarly than identical twins.

Identical twins will express the behaviour more similarly than fraternal twins.

There will be more similarity in the expression of the behaviour in either set of twins.

There will be little similarity in the expression of the behaviour in either set of twins.

The behaviour will be expressed as similarly by identical twins as it is by fraternal twins.