Which of the following is a simple sentence?
- A. Although it was raining, we decided to go for a walk.
- B. I went to the store and bought some milk.
- C. I went to the store because I needed some milk.
- D. I went to the store where I bought some milk and met my friend.
- I went to the store and bought some milk.
Please select one of the options to reveal the correct answer.