Parliament did not accord full refugee benefits to twelve of the recent immigrants because it believed that to do it rewards them for entering the country illegally.
doing so=according full refugee benefits to 12 of the recents immigrants. The pronoun "it" cannot modify the such a long phrase, usually "it" modifies the noun it fills in for. The use of "would" is justified because the action is abstract in nature.
So, D touches bases on both of these.
Hard work is the main determinant of success