Sunglasses: Sunglasses are commonly used during summer to protect our eyes from the bright sunlight. They help in reducing glare and protecting our eyes from harmful UV rays. Sunglasses can also be a fashion accessory.

Cotton clothes: Cotton clothes are lightweight and breathable, making them ideal for summer. They allow air to flow through the fabric, keeping us cool and comfortable. Cotton also absorbs moisture, helping to keep our skin dry during hot and humid weather.

Jacket: Jackets are typically not used during summer as they are designed to provide warmth in colder temperatures. Wearing a jacket during summer can make us feel uncomfortable and overheated. However, there might be some specific situations or regions where a light jacket might be needed during cool summer evenings or in air-conditioned environments.

Fans: Fans are commonly used during summer to circulate air and create a cooling effect. They help in reducing the feeling of heat by promoting evaporation of sweat from our skin. Fans can be used both indoors and outdoors to provide relief from the hot weather.

Correct answer: The correct answer is option 'C' - Jacket. Jackets are not typically used during summer as they are designed for colder temperatures and can make us feel uncomfortable in hot weather. However, it is important to note that there might be specific situations or regions where a light jacket might still be needed during summer.