What is nationalism? a: loyalty to a group with whom one shares a common history, culture, and/or religion b: loyalty based on geographic location c: a sense of belonging that is based on a written document like a constitution d: a feeling of belonging to a group that is highly educated and wealthy

A: loyalty to a group with whom one shares a common history, culture, and/or religion

Salutations!

Nationalism is a feeling of love to one's country. Having the feeling of patriotism or love means a citizen from the same country, religion etc. Nationalism is widely felt in militaries, forces etc. From your following options, the correct answer is: a loyalty to a group with whom one shares a common history, culture and/or religion.

Thus, your answer is option A.

Hope I  helped (:

have a great day!