A brand or part of a brand which is given legal protection is known as:

Option 1 -> A brand is the complete identity of a product including name, symbol, design, and reputation, but doesn't specifically refer to legal protection.

Option 2 -> A trademark is a brand or part of a brand that has been legally registered and protected, preventing unauthorized use by others.

Option 3 -> Brand name refers only to the word or letter elements that can be vocalized, but may not have legal protection.

Option 4 -> Brand mark is the visual symbol, design, or logo part of a brand that cannot be spoken, but isn't necessarily legally protected.

Hence, Option 2: Trade Mark -> A trademark is specifically defined as a brand or any part of a brand (name, symbol, design) that is given legal protection through registration, which grants exclusive rights to use it and prevents others from using identical or confusingly similar marks -> correct