Select the most appropriate option to fill in the blank.

The migrant crisis led several states to ______ existing labour laws in order to improve their condition.

amend

The most appropriate option to fill in the blank is amend.

The word amend means to make changes to something, especially to improve it. In this case, the migrant crisis led several states to make changes to existing labor laws in order to improve the condition of migrants.

The other options do not make sense in the context of the sentence.

• Introduce means to bring something new into existence.
• Initiate means to start something.
• Abandon means to give up or leave something.