Greater Jihad is best defined as:

The correct interpretation of Greater Jihad is indeed the internal struggle to live righteously. In Islamic theology, Greater Jihad refers to the personal, spiritual effort each individual makes to improve themselves, strive for righteousness, and maintain a strong moral compass. It encompasses striving against one’s own desires and weaknesses to adhere to the principles of Islam more faithfully.

Greater Jihad is often contrasted with Lesser Jihad, which can include external conflicts or struggles, but the emphasis is primarily on the internal battle against sin and the pursuit of personal and spiritual betterment. This struggle is seen as an essential part of a devout Muslim's life, reflecting a commitment to faith, self-improvement, and adherence to the tenets of Islam.

The other options do not accurately capture the essence of Greater Jihad. External conflicts would relate more to Lesser Jihad, while financial sacrifices for charity and political activism are important forms of communal engagement but are not the focus of Greater Jihad. Therefore, the understanding of Greater Jihad as an internal struggle aligns perfectly with Islamic teachings on the importance of personal growth and ethical living.