Meaning: 'Build' means to create or develop something over time, in this case, a mental image of the size of the feet.

Wrong options:

• pick: 'Pick' implies selecting or choosing, which does not convey the idea of constructing a comprehensive understanding of size.
• grow: 'Grow' suggests a natural increase or development, which is not appropriate for the context of forming a picture.
• set: 'Set' typically means to place or establish something, which does not fit the context of developing an understanding.

Correct answer: exactly

Explanation: The adverb 'exactly' is appropriate here as it specifies the precision of the fit, aligning with the context of ensuring the shoes fit perfectly. It modifies the verb 'fit' and maintains the formal tone of the text.

Meaning: 'Exactly' means precisely or accurately, indicating that the shoes will fit the wearer without any discrepancies.

Wrong options:

• absolutely: 'Absolutely' conveys a sense of totality but lacks the precision required in this context.
• completely: 'Completely' suggests fullness but does not emphasize the precision of fit as 'exactly' does.
• totally: 'Totally' implies an all-encompassing nature, which is less specific than 'exactly' in terms of fitting.

Correct answer: cause

Explanation: The verb 'cause' fits grammatically and contextually as it indicates the action of bringing about blisters, which aligns with the negative outcome being discussed. It is the most suitable choice in terms of causation.

Meaning: 'Cause' means to make something happen, in this case, the occurrence of blisters due to ill-fitting shoes.

Wrong options:

• provoke: 'Provoke' suggests inciting a reaction, which is less direct than 'cause' in this context.
• form: 'Form' implies creating or shaping, which does not directly relate to the emergence of blisters.
• initiate: 'Initiate' means to begin something, which does not fit the context of the shoes' effect on blisters.

Correct answer: performance

Explanation: The noun 'performance' is suitable here as it refers to how well an athlete performs, which is the focus of the sentence. It fits grammatically as the object of the verb 'help improve'.

Meaning: 'Performance' refers to how well someone does in a particular activity, especially in sports.

Wrong options:

• achievement: 'Achievement' refers to a completed goal or success, which does not directly relate to the ongoing action of improving.
• success: 'Success' implies a favorable outcome but does not capture the process of improvement as 'performance' does.
• winning: 'Winning' specifically refers to the act of coming first, which is a result rather than a measure of ongoing capability.

Correct answer: place

Explanation: The noun 'place' fits grammatically as it indicates a position or role that the system will find in other household items. It aligns with the context of integration into various products.

Meaning: 'Place' refers to a position or location where something can be used or found.

Wrong options:

• function: 'Function' implies a specific role or purpose, which does not fit the context of finding a position in household items.
• part: 'Part' suggests a component of something larger, which does not convey the idea of a broader application as 'place' does.
• way: 'Way' indicates a method or manner, which is less specific than 'place' in terms of integration into products.

Correct answer: shape

Explanation: The verb 'shape' fits grammatically as it indicates the action of forming or adjusting the tools to fit the user's hand, aligning well with the context of customization for better grip.

Meaning: 'Shape' means to form or mold something into a particular configuration, in this case, adapting tools to the user's hand.

Wrong options:

• change: 'Change' is too broad and does not specifically convey the idea of forming something to fit a particular need.
• respond: 'Respond' implies reacting to something, which does not fit the context of actively forming tools to the user's hand.
• convert: 'Convert' suggests a transformation into a different state, which is not the intended meaning in this context.