Select the most appropriate option to fill in the blank.

The activist is working really hard and was determined to __________ for this cause.

move heaven and earth

The most appropriate option to fill in the blank is move heaven and earth.

• Have feet of clay means to have flaws or weaknesses despite appearing perfect. It does not make sense in the context of the sentence because it does not describe the activist's determination.
• Blow his own trumpet means to boast about one's accomplishments. It does not make sense in the context of the sentence because it does not describe the activist's determination.
• Keep the wolf from the door means to make sure that you have enough money to survive. It does not make sense in the context of the sentence because it does not describe the activist's determination.
• Move heaven and earth means to do everything possible to achieve something. It is the most appropriate option to fill in the blank because it describes the activist's determination to succeed in their cause.