Select the most appropriate option to fill in the blank.

The majority ______ that the country can progress under able leadership.

believes

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

The sentence is about the majority of people believing that the country can progress under able leadership. The verb "believes" is used in the present tense because it is a general statement about the majority of people.

The other options are incorrect.

• Believe is the infinitive form of the verb "believe." It is not appropriate to use the infinitive form in this context.
• Is believing is the present progressive tense of the verb "believe." It is not appropriate to use the present progressive tense in this context because it is not a continuous action.
• Have believed is the past perfect tense of the verb "believe." It is not appropriate to use the past perfect tense in this context because it is not referring to a specific event in the past.