Meaning: 'Center' refers to the middle point or the most important place where activities occur.

Wrong options:

• backed: 'Backed' is a verb that means to support or assist, which does not fit grammatically as it cannot serve as a noun in this context.
• movements: 'Movements' is a noun that refers to organized efforts or campaigns, but it does not fit the blank as it is already the correct answer for the second blank.
• courses: 'Courses' is a noun that typically refers to a series of classes or a path, which does not relate to the context of being a focal point for political and social activities.
• shaken: 'Shaken' is a past participle verb that means to disturb or unsettle, which does not fit as it cannot serve as a noun in this context.
• supported: 'Supported' is a verb that means to provide assistance or backing, which does not fit grammatically as it cannot serve as a noun in this context.

Correct answer: movements

Explanation: The term 'movements' is a plural noun that refers to organized efforts or campaigns aimed at social or political change. It fits contextually as it describes the various activities that took place in Paris, aligning with the overall theme of political and social change.

Meaning: 'Movements' refers to organized groups or campaigns that seek to bring about change in society or politics.

Wrong options:

• backed: 'Backed' is a verb that means to support or assist, which does not fit as it does not describe a type of activity or campaign.
• courses: 'Courses' is a noun that typically refers to a series of classes or a path, which does not relate to the context of political and social activities.
• center: 'Center' is a noun that refers to the focal point of activity, but it does not fit in this blank as it is already the correct answer for the first blank.
• shaken: 'Shaken' is a past participle verb that means to disturb or unsettle, which does not fit as it does not describe a type of activity or campaign.
• supported: 'Supported' is a verb that means to provide assistance or backing, which does not fit as it does not describe a type of activity or campaign.

Correct answer: shaken

Explanation: The word 'shaken' is a past participle that describes the action of being disturbed or unsettled. In this context, it complements the idea of tradition being challenged, fitting grammatically and contextually as it describes the impact of those years on traditional art.

Meaning: 'Shaken' refers to being disturbed or unsettled, particularly in the context of established norms or traditions.

Wrong options:

• backed: 'Backed' is a verb that means to support or assist, which does not fit as it does not describe the action of challenging or disturbing tradition.
• movements: 'Movements' is a noun that refers to organized efforts or campaigns, which does not fit in this blank as it is already the correct answer for the second blank.
• courses: 'Courses' is a noun that typically refers to a series of classes or a path, which does not relate to the context of challenging tradition.
• center: 'Center' is a noun that refers to the focal point of activity, which does not fit in this blank as it does not describe the action of challenging or disturbing tradition.
• supported: 'Supported' is a verb that means to provide assistance or backing, which does not fit as it does not describe the action of challenging or disturbing tradition.