The conditions described in this passage directly resulted in 1.Ireland invading Britain
2.Millions of Irish emigrating to the United States
3.Most landlords forgiving the rent the Irish owed
4.Britain agreeing to withdraw from Ireland

It should be 2

Explanation:

The Irish didn't invade Britain nor did Britain agree to withdraw from Ireland. The landlords forgiving the rent the Irish owed doesn't make any sense and millions of Irish did emigrate to the United States.

2018 means 2018 ce or common era

there have been other eras too including bce, which included way more years.