1. is 2. exercise 3. to 4. health 5. essential A. 25413 B. 23541 C. 21453 D. 21534

The correct answer is 21534.

• Is is a verb that is used to ask questions or make statements.
• Exercise is a noun that refers to physical activity that is done to maintain or improve health.
• To is a preposition that is used to indicate a purpose or destination.
• Health is a noun that refers to the state of being well and free from illness.
• Essential is an adjective that means necessary or indispensable.

In this case, the question is “Is exercise essential to health?” The answer is yes, exercise is essential to health. Exercise helps to maintain a healthy weight, reduce the risk of chronic diseases, and improve mental health.