"Keep an eye on Esther. I'll be back in a second," Joy Warren said to her three-year-old son Stephen, who was sitting in the back of the Buick. She didn't like leaving the children alone in the car, but the baby was sleeping soundly. And it would only be a moment. She had hardly walked 40 yards when she saw the car moving. It headed straight towards the river. Unable to swim, Joy shouted, "My babies are in that car!" Daniel Whitehead, a 17-year-old student, was walking by the river when the Buick crashed into the water just yards ahead .Without thinking, Daniel jumped in. Though a competitive swimmer, he was shocked by the icy chill. Two minutes earlier, Skip Womack had pulled to a halt as the Buick ran in front of him. Now seeing it hit the water and hearing Joy's cries, Skip got out of his truck and jumped into the water. He had only one thought: If I don't get them out, they'll drown. Daniel reached the car and grabbed a door handle. But the water was only four inches beneath the window, and the door wouldn't open. With one powerful punch, Daniel and Skip broke a window. Daniel reached inside and lifted Stephen out. He placed him on his back and set out for shore. At the same time, Skip squeezed himself through the window .He managed to free Esther from beneath her seat belt. After he got out of the car with the baby, he held her over the water and swam toward the shore. All this took place just seconds before the Buick disappeared beneath the water. Later, driving home, Skip thought of his wife and children--how close he'd come to leaving them behind. He thought of the miracle he'd lived through, and how two children were still alive because he and Daniel happened to be in the right place at the right time. Daniel and Skip, who saved the lives of the two kids,   _  .
had been good friends were two close friends of Joy Warren's were Joy Warren's neighbors were strangers before the accident
Question: "Keep an eye on Esther. I'll be back in a second," Joy Warren said to her three-year-old son Stephen, who was sitting in the back of the Buick. She didn't like leaving the children alone in the car, but the baby was sleeping soundly. And it would only be a moment. She had hardly walked 40 yards when she saw the car moving. It headed straight towards the river. Unable to swim, Joy shouted, "My babies are in that car!" Daniel Whitehead, a 17-year-old student, was walking by the river when the Buick crashed into the water just yards ahead .Without thinking, Daniel jumped in. Though a competitive swimmer, he was shocked by the icy chill. Two minutes earlier, Skip Womack had pulled to a halt as the Buick ran in front of him. Now seeing it hit the water and hearing Joy's cries, Skip got out of his truck and jumped into the water. He had only one thought: If I don't get them out, they'll drown. Daniel reached the car and grabbed a door handle. But the water was only four inches beneath the window, and the door wouldn't open. With one powerful punch, Daniel and Skip broke a window. Daniel reached inside and lifted Stephen out. He placed him on his back and set out for shore. At the same time, Skip squeezed himself through the window .He managed to free Esther from beneath her seat belt. After he got out of the car with the baby, he held her over the water and swam toward the shore. All this took place just seconds before the Buick disappeared beneath the water. Later, driving home, Skip thought of his wife and children--how close he'd come to leaving them behind. He thought of the miracle he'd lived through, and how two children were still alive because he and Daniel happened to be in the right place at the right time. Daniel and Skip, who saved the lives of the two kids,   _  .
A. had been good friends
B. were two close friends of Joy Warren's
C. were Joy Warren's neighbors
D. were strangers before the accident
Answer: